Document and Entity Information Document - shares |
3 Months Ended | |
|---|---|---|
Mar. 31, 2018 |
May 01, 2018 |
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| Entity Information [Line Items] | ||
| Document Type | 10-Q | |
| Amendment Flag | false | |
| Document Period End Date | Mar. 31, 2018 | |
| Document Fiscal Year Focus | 2018 | |
| Document Fiscal Period Focus | Q1 | |
| Trading Symbol | WR | |
| Entity Registrant Name | WESTAR ENERGY INC /KS | |
| Entity Central Index Key | 0000054507 | |
| Current Fiscal Year End Date | --12-31 | |
| Entity Filer Category | Large Accelerated Filer | |
| Entity Common Stock, Shares Outstanding | 142,233,136 |
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- Definition If the value is true, then the document is an amendment to previously-filed/accepted document. No definition available.
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- Definition End date of current fiscal year in the format --MM-DD. No definition available.
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- Definition This is focus fiscal period of the document report. For a first quarter 2006 quarterly report, which may also provide financial information from prior periods, the first fiscal quarter should be given as the fiscal period focus. Values: FY, Q1, Q2, Q3, Q4, H1, H2, M9, T1, T2, T3, M8, CY. No definition available.
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- Definition This is focus fiscal year of the document report in CCYY format. For a 2006 annual report, which may also provide financial information from prior periods, fiscal 2006 should be given as the fiscal year focus. Example: 2006. No definition available.
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- Definition The end date of the period reflected on the cover page if a periodic report. For all other reports and registration statements containing historical data, it is the date up through which that historical data is presented. If there is no historical data in the report, use the filing date. The format of the date is CCYY-MM-DD. No definition available.
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- Definition The type of document being provided (such as 10-K, 10-Q, 485BPOS, etc). The document type is limited to the same value as the supporting SEC submission type, or the word "Other". No definition available.
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- Definition A unique 10-digit SEC-issued value to identify entities that have filed disclosures with the SEC. It is commonly abbreviated as CIK. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Indicate number of shares or other units outstanding of each of registrant's classes of capital or common stock or other ownership interests, if and as stated on cover of related periodic report. Where multiple classes or units exist define each class/interest by adding class of stock items such as Common Class A [Member], Common Class B [Member] or Partnership Interest [Member] onto the Instrument [Domain] of the Entity Listings, Instrument. No definition available.
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- Definition Indicate whether the registrant is one of the following: (1) Large Accelerated Filer, (2) Accelerated Filer, (3) Non-accelerated Filer, (4) Smaller Reporting Company (Non-accelerated) or (5) Smaller Reporting Accelerated Filer. Definitions of these categories are stated in Rule 12b-2 of the Exchange Act. This information should be based on the registrant's current or most recent filing containing the related disclosure. No definition available.
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition The exact name of the entity filing the report as specified in its charter, which is required by forms filed with the SEC. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Trading symbol of an instrument as listed on an exchange. No definition available.
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- Definition Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The noncurrent portion of the reserve for accumulated deferred investment tax credits as of the balance sheet date. This is the remaining investment credit, which will reduce the cost of services collected from ratepayers by a ratable portion over the investment's regulatory life. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Value received from shareholders in common stock-related transactions that are in excess of par value or stated value and amounts received from other stock-related transactions. Includes only common stock transactions (excludes preferred stock transactions). May be called contributed capital, capital in excess of par, capital surplus, or paid-in capital. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Noncurrent portion of the carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Sum of the carrying amounts as of the balance sheet date of all assets that are expected to be realized in cash, sold, or consumed within one year (or the normal operating cycle, if longer). Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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| X | ||||||||||
- Definition Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Represents the caption on the face of the balance sheet to indicate that the entity has entered into (1) purchase or supply arrangements that will require expending a portion of its resources to meet the terms thereof, and (2) is exposed to potential losses or, less frequently, gains, arising from (a) possible claims against a company's resources due to future performance under contract terms, and (b) possible losses or likely gains from uncertainties that will ultimately be resolved when one or more future events that are deemed likely to occur do occur or fail to occur. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Aggregate par or stated value of issued nonredeemable common stock (or common stock redeemable solely at the option of the issuer). This item includes treasury stock repurchased by the entity. Note: elements for number of nonredeemable common shares, par value and other disclosure concepts are in another section within stockholders' equity. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The fair value of investments held in a trust fund to pay for the costs of decontaminating and decommissioning facilities, whether such amount is presented as a separate caption or as a parenthetical disclosure on the balance sheet. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences, with jurisdictional netting and classified as noncurrent. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Carrying value as of the balance sheet date of [accrued] interest payable on all forms of debt, including trade payables, that has been incurred and is unpaid. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of liabilities and equity items, including the portion of equity attributable to noncontrolling interests, if any. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Total obligations incurred as part of normal operations that are expected to be paid during the following twelve months or within one business cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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- Definition Amount of obligation due after one year or beyond the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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| X | ||||||||||
- Definition Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which is directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent (that is, noncontrolling interest, previously referred to as minority interest). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of current assets classified as other. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of noncurrent assets classified as other. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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- Definition Amount of liabilities classified as other, due within one year or the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of liabilities classified as other, due after one year or the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of asset related to consideration paid in advance for costs that provide economic benefits within a future period of one year or the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Carrying amount as of the balance sheet date of capitalized costs of regulated entities that are expected to be recovered through revenue sources within one year or the normal operating cycle, if longer. Such costs are capitalized if they meet both of the following criteria: a. It is probable that future revenue in an amount at least equal to the capitalized cost will result from inclusion of that cost in allowable costs for rate-making purposes. b. Based on available evidence, the future revenue will be provided to permit recovery of the previously incurred cost rather than to provide for expected levels of similar future costs. If the revenue will be provided through an automatic rate-adjustment clause, this criterion requires that the regulator's intent clearly be to permit recovery of the previously incurred cost. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Carrying amount as of the balance sheet date of capitalized costs of regulated entities that are not expected to be recovered through revenue sources within one year or the normal operating cycle if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The amount for the individual regulatory current liability as itemized in a table of regulatory current liabilities as of the end of the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The amount for the individual regulatory noncurrent liability as itemized in a table of regulatory noncurrent liabilities as of the end of the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The cumulative amount of the reporting entity's undistributed earnings or deficit. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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- Definition Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Carrying value as of the balance sheet date of obligations incurred and payable for statutory income, sales, use, payroll, excise, real, property and other taxes. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The noncurrent liability recognized in the balance sheet associated with defined benefit pension plans, other post-retirement benefit plans and other general benefit plans. No definition available.
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- Definition Total Other Assets No definition available.
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- Details
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Consolidated Balance Sheets Parenthetical (Parentheticals) - USD ($) $ in Thousands |
Mar. 31, 2018 |
Dec. 31, 2017 |
|---|---|---|
| CURRENT ASSETS: | ||
| Allowance for doubtful accounts | $ 9,288 | $ 6,716 |
| Westar Energy, Inc. Shareholders' Equity: | ||
| Common stock, par value | $ 5 | $ 5 |
| Common stock, shares authorized | 275,000,000 | 275,000,000 |
| Common stock, shares issued | 142,233,103 | 142,094,275 |
| Common stock, shares outstanding | 142,233,103 | 142,094,275 |
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- Definition A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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- Definition Face amount or stated value per share of common stock. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The maximum number of common shares permitted to be issued by an entity's charter and bylaws. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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- Definition Aggregate dividends declared during the period for each share of common stock outstanding. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Total costs of sales and operating expenses for the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The aggregate net amount of depreciation, amortization, and accretion recognized during an accounting period. As a noncash item, the net amount is added back to net income when calculating cash provided by or used in operations using the indirect method. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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- Definition The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of the cost of borrowed funds accounted for as interest expense. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The aggregate amount of income from investments (for example, dividends) not considered a component of the entity's core operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The portion of profit or loss for the period, net of income taxes, which is attributable to the parent. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of Net Income (Loss) attributable to noncontrolling interest. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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- References No definition available.
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| X | ||||||||||
- Definition The net result for the period of deducting operating expenses from operating revenues. No definition available.
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- Definition Amount of expense related to nonoperating activities, classified as other. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of income related to nonoperating activities, classified as other. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition All taxes not related to income of the entity or excise or sales taxes levied on the revenue of the entity that are not reported elsewhere. These taxes could include production, real estate, personal property, and pump tax. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of operating expense for routine plant maintenance, repairs and operations of regulated operation. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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- Definition Fuel and purchased power expense incurred that are directly related to goods produced and sold. No definition available.
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- Definition Network Transmission Cost No definition available.
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- References No definition available.
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| X | ||||||||||
- Definition Amount of cash paid during the period to settle an asset retirement obligation. Amounts paid to settle an asset retirement obligation are generally included in the operating section of the Statement of Cash Flows. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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| X | ||||||||||
- Definition Amount of increase (decrease) in cash and cash equivalents. Cash and cash equivalents are the amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Includes effect from exchange rate changes. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage. Excludes amount for disposal group and discontinued operations. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of deferred income tax expense (benefit) and income tax credits. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The aggregate net amount of depreciation, amortization, and accretion recognized during an accounting period. As a noncash item, the net amount is added back to net income when calculating cash provided by or used in operations using the indirect method. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition The increase (decrease) during the reporting period in the aggregate amount of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition The increase (decrease) during the reporting period in amount due within one year (or one business cycle) from customers for the credit sale of goods and services. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition The increase (decrease) during the reporting period of all taxes owed but not paid, including income, property and other taxes. No definition available.
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| X | ||||||||||
- Definition The increase (decrease) during the reporting period in the aggregate value of all inventory held by the reporting entity, associated with underlying transactions that are classified as operating activities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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| X | ||||||||||
- Definition Amount of increase (decrease) in current liabilities classified as other. No definition available.
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| X | ||||||||||
- Definition Amount of increase (decrease) in operating assets classified as other. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of increase (decrease) in operating liabilities classified as other. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of increase (decrease) in prepaid expenses, and assets classified as other. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition The change in cash surrender or contract value during the period which adjusted the amount of premiums paid in determining the expense or income recognized under the contract for the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Decrease in noncontrolling interest balance from payment of dividends or other distributions by the non-wholly owned subsidiary or partially owned entity, included in the consolidation of the parent entity, to the noncontrolling interest holders. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- References No definition available.
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| X | ||||||||||
- Definition Amount of cash inflow (outflow) of financing activities, excluding discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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| X | ||||||||||
- Definition Amount of cash inflow (outflow) of investing activities, excluding discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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| X | ||||||||||
- Definition Amount of cash inflow (outflow) from operating activities, excluding discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of cash (inflow) outflow from investing activities classified as other. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Cash outflow in the form of capital distributions and dividends to common shareholders, preferred shareholders and noncontrolling interests. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Cash outflow for purchase of trading, available-for-sale securities and held-to-maturity securities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition The cash inflow from the additional capital contribution to the entity. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of cash inflow for proceeds from settlement of corporate-owned life insurance policy, classified as investing activities. Includes, but is not limited to, bank-owned life insurance policy. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of cash inflow (outflow) from financing activities classified as other. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The net cash inflow or outflow for borrowing having initial term of repayment within one year or the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition The cash inflow associated with the aggregate amount received by the entity through sale or maturity of marketable securities (held-to-maturity or available-for-sale) during the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The component of the allowance for funds used during construction during the period based on an assumed rate of return on equity funds used in financing the construction of regulated assets. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition The cash outflow for the obligation for a lease meeting the criteria for capitalization (with maturities exceeding one year or beyond the operating cycle of the entity, if longer). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of cash restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition The portion of the deferred gain that was recognized in the current period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition The amortization of various items related to corporate-owned life insurance policies. No definition available.
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| X | ||||||||||
- Definition The current period expense charged against earnings for the amortization of capitalized nuclear fuel used to generate electricity. No definition available.
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- Definition Corporate-owned life insurance income No definition available.
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| X | ||||||||||
- Definition The cash inflow from borrowings against the cash surrender value of corporate-owned life insurance polices. No definition available.
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| X | ||||||||||
- Definition The cash outflow associated with the repayment of borrowings against the cash surrender value of corporate-owned life insurance polices. No definition available.
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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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| X | ||||||||||
- Definition The amount of adjustment to stockholders' equity associated with an employee's income tax withholding obligation as part of a net-share settlement of a share-based award. No definition available.
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| X | ||||||||||
- Definition Amount of increase to additional paid-in capital (APIC) resulting from recognition of equity-based compensation for restricted stock units. No definition available.
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| X | ||||||||||
- Definition Amount of paid and unpaid common stock dividends declared with the form of settlement in cash, stock and payment-in-kind (PIK). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Decrease in noncontrolling interest balance from payment of dividends or other distributions by the non-wholly owned subsidiary or partially owned entity, included in the consolidation of the parent entity, to the noncontrolling interest holders. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Number of shares issued which are neither cancelled nor held in the treasury. No definition available.
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| X | ||||||||||
- Definition Number of new stock issued during the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Equity impact of the value of new stock issued during the period. Includes shares issued in an initial public offering or a secondary public offering. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Issuance Of Stock For Compensation And Reinvested Dividends No definition available.
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- Definition Issuance Of Stock For Compensation And Reinvested Dividends, Shares No definition available.
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Consolidated Statements Of Changes in Equity Parenthetical (Parentheticals) - $ / shares |
3 Months Ended | |
|---|---|---|
Mar. 31, 2018 |
Mar. 31, 2017 |
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| DIVIDENDS DECLARED PER COMMON SHARE | $ 0.40 | $ 0.40 |
| X | ||||||||||
- Definition Aggregate dividends declared during the period for each share of common stock outstanding. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Description Of Business |
3 Months Ended |
|---|---|
Mar. 31, 2018 | |
| Organization, Consolidation and Presentation of Financial Statements [Abstract] | |
| Description Of Business | DESCRIPTION OF BUSINESS We are the largest electric utility in Kansas. Unless the context otherwise indicates, all references in this Quarterly Report on Form 10-Q to “the Company,” “we,” “us,” “our” and similar words are to Westar Energy, Inc. and its consolidated subsidiaries. The term “Westar Energy” refers to Westar Energy, Inc., a Kansas corporation incorporated in 1924, alone and not together with its consolidated subsidiaries. We provide electric generation, transmission and distribution services to approximately 710,000 customers in Kansas. Westar Energy provides these services in central and northeastern Kansas, including the cities of Topeka, Lawrence, Manhattan, Salina and Hutchinson. Kansas Gas and Electric Company (KGE), Westar Energy’s wholly-owned subsidiary, provides these services in south-central and southeastern Kansas, including the city of Wichita. Both Westar Energy and KGE conduct business using the name Westar Energy. Our corporate headquarters is located at 818 South Kansas Avenue, Topeka, Kansas 66612. |
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- Definition The entire disclosure for the nature of an entity's business, major products or services, principal markets including location, and the relative importance of its operations in each business and the basis for the determination, including but not limited to, assets, revenues, or earnings. For an entity that has not commenced principal operations, disclosures about the risks and uncertainties related to the activities in which the entity is currently engaged and an understanding of what those activities are being directed toward. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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Summary Of Significant Accounting Policies |
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| Accounting Policies [Abstract] | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Summary Of Significant Accounting Policies | SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Principles of Consolidation We prepare our unaudited condensed consolidated financial statements in accordance with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, certain information and footnote disclosures normally included in financial statements presented in accordance with generally accepted accounting principles (GAAP) for the United States of America have been condensed or omitted. Our condensed consolidated financial statements include all operating divisions, majority owned subsidiaries and a variable interest entity (VIE) of which we maintain a controlling interest or are the primary beneficiary reported as a single reportable segment. Undivided interests in jointly-owned generation facilities are included on a proportionate basis. Intercompany accounts and transactions have been eliminated in consolidation. In our opinion, all adjustments, consisting of normal recurring adjustments considered necessary for a fair presentation of the condensed consolidated financial statements, have been included. The accompanying condensed consolidated financial statements and notes should be read in conjunction with the consolidated financial statements and notes included in our 2017 Form 10-K. Use of Management’s Estimates When we prepare our condensed consolidated financial statements, we are required to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenues and expenses, and related disclosure of contingent assets and liabilities at the date of our condensed consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. We evaluate our estimates on an ongoing basis, including those related to depreciation, unbilled revenue, valuation of investments, forecasted fuel costs included in our retail energy cost adjustment billed to customers, income taxes, pension and post-retirement benefits, our asset retirement obligations (AROs) including the decommissioning of Wolf Creek, environmental issues, VIEs, contingencies and litigation. Actual results may differ from those estimates under different assumptions or conditions. The results of operations for the three months ended March 31, 2018, are not necessarily indicative of the results to be expected for the full year. Fuel Inventory and Supplies We state fuel inventory and supplies at average cost. Following are the balances for fuel inventory and supplies stated separately.
Allowance for Funds Used During Construction Allowance for funds used during construction (AFUDC) represents the allowed cost of capital used to finance utility construction activity. We compute AFUDC by applying a composite rate to qualified construction work in progress. We credit other income (for equity funds) and interest expense (for borrowed funds) for the amount of AFUDC capitalized as construction cost on the accompanying condensed consolidated statements of income as follows:
Earnings Per Share We have participating securities in the form of unvested restricted share units (RSUs) with nonforfeitable rights to dividend equivalents that receive dividends on an equal basis with dividends declared on common shares. As a result, we apply the two-class method of computing basic and diluted earnings per share (EPS). To compute basic EPS, we divide the earnings allocated to common stock by the weighted average number of common shares outstanding. Diluted EPS includes the effect of issuable common shares resulting from our RSUs with forfeitable rights to dividend equivalents. We compute the dilutive effect of potential issuances of common shares using the treasury stock method. The following table reconciles our basic and diluted EPS from net income.
_______________ (a)We had no antidilutive securities for the three months ended March 31, 2018 and 2017. Supplemental Cash Flow Information
Revenue Recognition Revenue is recognized primarily at the time we deliver electricity or provide transmission service to customers. The time of delivery of electricity is generally when our obligation to provide service is satisfied. Sales tax and franchise fees that we collect concurrent with revenue-producing activities are excluded from revenue. For more information on revenue recognition, see Note 4, “Revenue.” We determine the amount of electricity delivered to customers through systematic monthly readings of customer meters. At the end of each month, we estimate how much electricity we have delivered since the prior meter reading and record the corresponding unbilled revenue. Our unbilled revenue estimate is affected by factors including energy demand, weather, line losses and changes in the composition of customer classes. We recorded estimated unbilled revenue of $68.2 million and $76.7 million as of March 31, 2018, and December 31, 2017, respectively. Allowance for Doubtful Accounts We determine our allowance for doubtful accounts based on the age of our receivables. We charge receivables off when they are deemed uncollectible, which is based on a number of factors including specific facts surrounding an account and management’s judgment. For the three months ended March 31, 2018 and 2017, we recorded bad debt expense related to contracts with customers of $4.0 million and $3.2 million, respectively. New Accounting Pronouncements We prepare our condensed consolidated financial statements in accordance with GAAP for the United States of America. To address current issues in accounting, the Financial Accounting Standards Board (FASB) and the Securities and Exchange Commission (SEC) issued the following new accounting guidance that may affect our accounting and/or disclosure. Compensation - Retirement Benefits In March 2017, the FASB issued Accounting Standard Update (ASU) No. 2017-07, which requires employers to disaggregate the service cost component from other components of net periodic benefit costs and to disclose the amounts of net periodic benefit costs that are included in each income statement line item. The standard requires employers to report the service cost component in the same line item as other compensation costs and to report the other components of net periodic benefit costs (which include interest costs, expected return on plan assets, amortization of prior service cost or credits and actuarial gains and losses) separately and outside a subtotal of operating income. Of the components of net periodic benefit cost, only the service cost component will be eligible for capitalization as property, plant and equipment, which is applied prospectively. The other components of net periodic benefit costs that are no longer eligible for capitalization as property, plant and equipment will be recorded as a regulatory asset. The guidance changing the presentation in the statements of income is applied on a retrospective basis. The guidance permits and we elected upon adoption to use a practical expedient that allows us to use the amounts disclosed in Note 8, “Pension and Post-Retirement Benefit Plans,” for applying the retrospective presentation of the 2017 condensed consolidated statement of income. As a result, we retrospectively decreased operating, maintenance, and administrative expense by $5.0 million and increased other expense by $5.0 million for the three months ended March 31, 2017. The new standard is effective for annual periods beginning after December 15, 2017. We adopted the guidance for the Westar Energy pension and post-retirement benefit plans as of January 1, 2018, without a material impact on our condensed consolidated financial statements. Statement of Cash Flows In August 2016, the FASB issued ASU No. 2016-15, which clarifies how certain cash receipts and cash payments are presented and classified in the statement of cash flows. Among other clarifications, the guidance requires that cash proceeds received from the settlement of corporate-owned life insurance (COLI) policies be classified as cash inflows from investing activities and that cash payments for premiums on COLI policies may be classified as cash outflows for investing activities, operating activities or a combination of both. Retrospective application is required. We adopted the guidance effective January 1, 2018, which resulted in retrospective reclassification of cash proceeds of $1.3 million from the settlement of COLI policies from cash inflows from operating activities to cash inflows from investing activities for the three months ended March 31, 2017. In addition, cash payments of $0.9 million for premiums on COLI policies were reclassified from cash outflows used in operating activities to cash outflows used in investing activities for the same period. In November 2016, the FASB issued ASU No. 2016-18, which requires that statement of cash flows explain the change for the period of restricted cash and restricted cash equivalents along with cash and cash equivalents. The guidance requires a retrospective transition method and is effective for fiscal years beginning after December 15, 2017. We adopted the guidance effective January 1, 2018. As a result, we adjusted amounts previously reported for cash and cash equivalents to include restricted cash which resulted in an increase to beginning and ending cash, cash equivalents and restricted cash of $0.1 million for the three months ended March 31, 2017. Leases In February 2016, the FASB issued ASU No. 2016-02, which requires a lessee to recognize right-of-use assets and lease liabilities, initially measured at present value of the lease payments, on its balance sheet for leases with terms longer than 12 months. Leases are to be classified as either financing or operating leases, with that classification affecting the pattern of expense recognition in the income statement. Accounting for leases by lessors is largely unchanged. The criteria used to determine lease classification will remain substantially the same, but will be more subjective under the new guidance. The guidance is effective for fiscal years beginning after December 15, 2018, with early adoption permitted. The guidance requires a modified retrospective approach for all leases existing at the earliest period presented, or entered into by the date of initial adoption, with certain practical expedients permitted. In 2016, we started evaluating our current leases to assess the initial impact on our consolidated financial results. We continue to evaluate the guidance and believe application of the guidance will result in an increase to our assets and liabilities on our consolidated balance sheet, with minimal impact to our consolidated statement of income. We also continue to monitor unresolved industry issues, including renewables and power purchase agreements, and will analyze the related impact. The standard permits an entity to elect a practical expedient for existing or expired contracts to forgo reassessing leases to determine whether each is in scope of the new standard and to forgo reassessing lease classification. We expect to elect this practical expedient upon implementation. Financial Instruments In January 2016, the FASB issued ASU No. 2016-01, which generally requires equity investments to be measured at fair value with changes in fair value recognized in net income. Under the new standard, equity securities are no longer to be classified as available-for-sale or trading securities. The guidance requires a modified retrospective transition method. This guidance is effective for fiscal years beginning after December 15, 2017; accordingly, we adopted the new standard on January 1, 2018, without a material impact on our condensed consolidated financial statements. Revenue Recognition In May 2014, the FASB issued ASU No. 2014-09, which addresses revenue from contracts with customers. Subsequent ASUs have been released providing modifications and clarifications to ASU No. 2014-09. The objective of the new guidance is to establish principles to report useful information to users of financial statements about the nature, amount, timing and uncertainty of revenue from contracts with customers. Under the new standard, an entity must identify the performance obligations in a contract, determine the transaction price and allocate the price to specific performance obligations to recognize the revenue when the obligation is completed. This guidance is effective for fiscal years beginning after December 15, 2017; accordingly, we adopted the new standard on January 1, 2018. The standard permits the use of either the retrospective application or modified retrospective method. We elected to use the modified retrospective method, which requires a cumulative-effect adjustment to be recorded on the balance sheet as of the beginning of 2018, if applicable, as if the standard had always been in effect. Adoption of the standard did not have a material impact to our condensed consolidated financial statements and, as a result, we recorded no cumulative effect of initially applying the standard. For more information on revenue recognition, see Note 4, “Revenue.” |
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- References No definition available.
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| X | ||||||||||
- Definition The entire disclosure for all significant accounting policies of the reporting entity. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Pending Merger Pending Merger (Notes) |
3 Months Ended | ||||||||||||||||||||||||||||||||||||||||
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Mar. 31, 2018 | |||||||||||||||||||||||||||||||||||||||||
| Business Combinations [Abstract] | |||||||||||||||||||||||||||||||||||||||||
| Business Combination Disclosure [Text Block] | PENDING MERGER On May 29, 2016, we entered into an agreement and plan of merger with Great Plains Energy that provided for the acquisition of us by Great Plains Energy. On April 19, 2017, the Kansas Corporation Commission (KCC) rejected the prior transaction. On July 9, 2017, we entered into an amended and restated agreement and plan of merger with Great Plains Energy that provides for a merger of equals between the two companies. Upon closing, each issued and outstanding share of our common stock will be converted into one share of common stock of a new holding company with a final name yet to be publicly announced. Upon closing, each issued and outstanding share of Great Plains Energy common stock will be converted into 0.5981 shares of common stock of the new holding company. Following completion of the merger, our shareholders are expected to own approximately 52.5% of the new holding company and Great Plains Energy’s shareholders are expected to own approximately 47.5% of the new holding company. The merger agreement includes certain restrictions and limitations on our ability to declare dividend payments. The merger agreement limits our quarterly dividends declared to $0.40 per share. The closing of the merger is subject to conditions including receipt of all required regulatory approvals from, among others, the Federal Energy Regulatory Commission (FERC), the NRC, the KCC, and the Missouri Public Service Commission (MPSC) (provided that such approvals do not result in a material adverse effect on Great Plains Energy or us, after giving effect to the merger, measured on the size and scale of Westar Energy and its subsidiaries, taken as a whole); effectiveness of the registration statement for the shares of the new holding company’s common stock to be issued to our shareholders and Great Plains Energy’s shareholders upon consummation of the merger and approval of the listing of such shares on the New York Stock Exchange; the receipt of tax opinions by us and Great Plains Energy that the merger will be treated as a non-taxable event for U.S. federal income tax purposes; there being no shares of Great Plains Energy preference stock outstanding; and Great Plains Energy having not less than $1.25 billion in cash or cash equivalents on its balance sheet. The closing of the merger is also subject to other standard conditions, such as accuracy of representations and warranties, compliance with covenants and the absence of a material adverse effect on either company. The merger agreement, which contains customary representations, warranties, and covenants, may be terminated by either party if the merger has not occurred by July 10, 2018. The termination date may be extended six months in order to obtain regulatory approvals. On August 25, 2017, we and Great Plains Energy filed a joint application with the KCC requesting approval of the merger. The KCC subsequently approved a procedural schedule that provides for a KCC order on the proposed merger by June 5, 2018, although under Kansas law the KCC has until June 21, 2018, to issue the order. On March 7, 2018, we, Great Plains Energy, the KCC staff, the Citizens’ Utility Ratepayer Board (CURB), and certain other intervenors entered into a non-unanimous settlement agreement to settle issues related to the joint application. The settlement agreement is subject to review and approval by the KCC. Components of the settlement agreement are summarized below. The settlement agreement, if approved, is expected to impact our 2018 rate review.
The settlement agreement also contains items that, if approved, are expected to impact the 2018 rate review for Kansas City Power & Light Company, a utility subsidiary of Great Plains Energy that operates in Kansas and Missouri. On August 31, 2017, we and Great Plains Energy applied for approval of the merger from the MPSC. On January 12, 2018, we, Great Plains Energy, the MPSC staff and certain other intervenors entered into a non-unanimous stipulation and agreement to settle issues related to the joint application. On March 8, 2018, the stipulation and agreement with MPSC staff was amended to include additional intervenors. The stipulation and agreement is subject to review and approval by the MPSC. We and Great Plains Energy each gained shareholder approval of the proposed merger on November 21, 2017. We and Great Plains Energy received early termination of the statutory waiting period under the Hart-Scott-Rodino Antitrust Improvements Act on December 12, 2017. We and Great Plains Energy received FERC approval of the merger on February 28, 2018. On March 12, 2018, Wolf Creek received approval from the NRC for an indirect transfer of control of Wolf Creek’s operating license. On March 19, 2018, we and Great Plains Energy received Federal Communications Commission consent for various license transfers that are deemed to occur with the merger. The amended and restated merger agreement provides that Great Plains Energy may be required to pay us a termination fee of $190.0 million if the agreement is terminated due to (i) failure to receive regulatory approval prior to July 10, 2018, subject to an extension of up to six months, (ii) a non-appealable regulatory order enjoining the merger or (iii) Great Plains Energy’s failure to close after all conditions precedent to closing have been satisfied. In addition, we may be required to pay Great Plains Energy a termination fee of $190.0 million if the agreement is terminated by us under certain circumstances. Similarly, Great Plains Energy may be required to pay us a termination fee of $190.0 million if the agreement is terminated by Great Plains Energy under certain circumstances. In connection with the merger, we have incurred, and expect to incur additional, merger-related expenses. These expenses are included in our operating, maintenance and administrative expenses. During the three months ended March 31, 2018 and 2017, we incurred approximately $0.4 million of merger-related expenses. In the event that the merger is consummated, we estimate merger-related expenses for investment banking, legal, and other professional services will be approximately $45.0 million. In addition, we expect to incur an estimated $40.0 million of expenses for accelerated stock-based compensation, voluntary severance plan payments and payments pursuant to change in control agreements. See also Note 11, “Legal Proceedings,” for more information on litigation related to the merger. |
| X | ||||||||||
- Definition The entire disclosure for a business combination (or series of individually immaterial business combinations) completed during the period, including background, timing, and recognized assets and liabilities. The disclosure may include leverage buyout transactions (as applicable). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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Revenue (Notes) |
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| Revenue from Contract with Customer [Abstract] | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Revenue from Contract with Customer [Text Block] | REVENUE Kansas law gives the KCC general regulatory authority over our retail prices, extensions and abandonments of service and facilities, the classification of accounts, the issuance of some securities and various other matters. We are also subject to the jurisdiction of FERC, which has authority over wholesale electricity sales, including prices and the transmission of electric power. Regulatory authorities have established various methods permitting adjustments to our prices for the recovery of costs, including the cost of invested capital. For portions of our cost of service, regulators allow us to adjust our prices periodically through the application of formulas that track changes in our costs, which reduces the time between making expenditures or investments and reflecting them in the prices we charge customers. However, for the remaining portions of our cost of service, we must file a general rate review, which lengthens the period of time between when we make and recover expenditures and a return on our investments. See Note 5, “Rate Matters and Regulation,” for information regarding our rate proceedings with the KCC and FERC and potential related refund obligations. We categorize revenue based on class of customer as discussed below. Retail Revenue We are the sole supplier of retail electricity within our service territory. We operate facilities necessary to generate, transmit and distribute electricity to our customers. We are required to provide electricity to customers in our service territory as requested by customers. Revenue is recognized over time as we satisfy our obligation, generally corresponding to the amount of electricity that we deliver to our customers. This method of recognizing revenue corresponds directly to the amount that we have the right to invoice our customers each month. Retail revenue is impacted by things such as weather, rate regulation, fuel costs, technology, customer behavior, the economy and competitive forces. Changing weather affects the amount of electricity our customers use as electricity sales are seasonal. As a summer peaking utility, the third quarter typically accounts for our greatest electricity sales. Hot summer temperatures and cold winter temperatures prompt more demand, especially among residential and commercial customers, and to a lesser extent, industrial customers. Mild weather reduces customer demand. We further classify retail customers as residential, commercial, industrial and other customers. Classification of customers as residential, commercial or industrial requires judgment and our classifications may be different from other companies. Assignment of tariffs is not dependent on classification. Other retail sales of electricity include lighting for public streets and highways. Wholesale Revenue We sell electricity and capacity (the ability to demand delivery of a maximum amount of electricity) at wholesale to electric cooperatives, municipalities, other electric utilities and RTOs, the prices for which are either based on cost or prevailing market prices as prescribed by FERC authority. We recognize revenue as we deliver the electricity and capacity that corresponds directly to the amount of consideration we expect to invoice. Revenues from these sales reduce retail electricity prices either annually through a formula or when base rates are determined at the time of a general rate review. Our wholesale revenues are impacted by, among other factors, demand, costs and availability of fuel and purchased power, price volatility, available generation capacity, transmission availability and weather. Our long-term contracts for wholesale capacity include variable transaction prices mostly based on peak demand for electricity and capacity of certain generating units. Terms on our long-term contracts for wholesale capacity expire between 2019 and 2039. Transmission Revenue We provide transmission service to the Southwest Power Pool, Inc. (SPP) by allowing it access to our transmission network. As new transmission lines are constructed, they are included in the transmission network available to the SPP. In exchange for providing access, the SPP pays us consideration determined by a formula rate approved by FERC, which includes the cost to construct and maintain the transmission lines and a return on our investment. The price for access to our transmission network is updated annually based on projected costs. Projections are updated to actual costs and the difference is included in subsequent year’s prices. We recognize revenue over time as we provide transmission service and as we have the right to invoice the SPP. Other Revenue from Contracts with Customers Other revenue derived from contracts with customers includes fees we earn for services provided to third parties and revenues earned by permitting other utilities to attach equipment to our utility poles. We recognize revenue when obligations under the terms of a contract with a customer are satisfied. The following table categorizes our revenue by class of customer.
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- References No definition available.
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- Definition The entire disclosure of revenue from contract with customer to transfer good or service and to transfer nonfinancial asset. Includes, but is not limited to, disaggregation of revenue, credit loss recognized from contract with customer, judgment and change in judgment related to contract with customer, and asset recognized from cost incurred to obtain or fulfill contract with customer. Excludes insurance and lease contracts. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Rate Matters And Regulation |
3 Months Ended |
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Mar. 31, 2018 | |
| Regulated Operations [Abstract] | |
| Rate Matters And Regulation | RATE MATTERS AND REGULATION KCC Proceedings In March 2018, the KCC issued an order allowing us to adjust our retail prices to include updated transmission costs as reflected in the transmission formula rate (TFR). The new prices were effective in April 2018 and are expected to increase our annual retail revenues by approximately $31.5 million. In February 2018, we filed a rate application with the KCC to update our prices to include, among other things, costs associated with the completion of Western Plains Wind Farm, expiration of wholesale contracts currently reflected in retail prices as offsets to our retail cost of service, expiration of the 10-year period for production tax credits from our initial wind investments and an updated depreciation study. This rate application also includes savings due to the recently passed federal Tax Cuts and Jobs Act (TCJA), savings achieved from refinancing debt and a portion of the savings from the proposed merger with Great Plains Energy. If our rate application were to be approved, we estimate the new prices would decrease our annual revenues by approximately $2.0 million in September 2018, followed by an increase in our annual revenues of approximately $54.0 million in February 2019. However, we, Great Plains Energy, the KCC staff, CURB and certain other intervenors entered into a non-unanimous settlement agreement related to our merger application, which includes commitments from certain parties to the settlement agreement to accept specific merger-contingent conditions or take particular positions in our rate review. See Note 3, “Pending Merger,” for additional information. If our rate application is approved with the merger-contingent conditions related to a 9.3% ROE and the limited amount of merger-related savings and transition costs included in our prices, then we estimate the new prices would decrease our annual revenues by approximately $37.0 million in September 2018, as compared to the approximately $2.0 million reduction originally requested. This reduction would be followed by an increase in our annual revenues of approximately $54.0 million in February 2019, as previously stated above. Our revenues would be further reduced due to the payment of bill credits in 2018 through 2022 as discussed in Note 3, “Pending Merger.” In January 2018, the KCC issued an order to investigate the effect of the TCJA on regulated utilities. The KCC stated the passage of the TCJA has the potential to significantly reduce the cost of service for utilities, and it may impact the regulatory assets and liabilities of Kansas utilities. Therefore, beginning in January 2018, the KCC directed each regulated electric public utility that is taxable at the corporate level to accrue monthly, in a deferred revenue account, the portion of its revenue representing the difference between: (1) the cost of service as approved by the KCC in its most recent rate review; and (2) the cost of service that would have resulted had the provision for federal corporate income taxes been based upon the corporate tax rate approved in the TCJA. The KCC also gave notice to taxable utilities operating in Kansas that the portion of their regulated revenue stream that reflects higher corporate tax rates should be considered interim and subject to refund, with interest. When the KCC’s evaluation of the impact of the TCJA is complete, if it is determined that a retail price decrease is proper and would have been proper as of the effective date of the TCJA, these amounts will be returned to customers. We believe it is probable that we will be required to return these amounts to customers. Therefore, we have recorded a $15.1 million regulatory liability as of March 31, 2018, and a corresponding decrease in revenues for the three months ended March 31, 2018. In December 2017, the KCC approved an order allowing us to adjust our prices to include costs incurred for property taxes. The new prices were effective in January 2018 and are expected to decrease our annual retail revenues by approximately $0.2 million. FERC Proceedings Our TFR that includes projected 2018 transmission capital expenditures and operating costs was effective in January 2018 and was expected to increase our annual transmission revenues by approximately $25.5 million. However, due to the passage of the TCJA, we requested permission from FERC to retroactively reflect the reduction in the federal corporate income tax rate in our 2018 prices. In April 2018, FERC granted our request and accordingly, we have recorded a $3.9 million regulatory liability as of March 31, 2018. This updated rate will provide the basis for a new request with the KCC to retroactively adjust our retail prices to include updated transmission costs as discussed above. We estimate the revised TFR will increase 2018 revenues by $2.3 million when compared to 2017. |
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- Definition The entire disclosure for public utilities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Financial Instruments and Investments |
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| Financial And Derivative Instruments and Investments [Abstract] | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Financial And Derivative Instruments And Investments | FINANCIAL INSTRUMENTS AND INVESTMENTS Values of Financial Instruments GAAP establishes a hierarchical framework for disclosing the transparency of the inputs utilized in measuring assets and liabilities at fair value. Our assessment of the significance of a particular input to the fair value measurement requires judgment and may affect the classification of assets and liabilities within the fair value hierarchy levels. In addition, we measure certain investments that do not have a readily determinable fair value at net asset value (NAV), which are not included in the fair value hierarchy. Further explanation of these levels and NAV is summarized below.
We record cash and cash equivalents, short-term borrowings and variable-rate debt on our condensed consolidated balance sheets at cost, which approximates fair value. We measure the fair value of fixed-rate debt, a level 2 measurement, based on quoted market prices for the same or similar issues or on the current rates offered for instruments of the same remaining maturities and redemption provisions. The recorded amount of accounts receivable and other current financial instruments approximates fair value. We measure fair value based on information available as of the measurement date. The following table provides the carrying values and measured fair values of our fixed-rate debt.
Recurring Fair Value Measurements The following table provides the amounts and their corresponding level of hierarchy for our assets that are measured at fair value.
We hold equity and debt investments that we classify as securities in a trust for the purpose of funding the decommissioning of Wolf Creek and maintain a Rabbi trust to manage funds for the benefit of certain retired executive officers. We record net realized and unrealized gains and losses on the Nuclear Decommissioning Trust (NDT) in regulatory liabilities on our condensed consolidated balance sheets. We include net realized and unrealized gains or losses on the Rabbi trust in investment earnings on our condensed consolidated statements of income. For the three months ended March 31, 2018 and 2017, we recorded net unrealized losses of $0.1 million and net unrealized gains of $9.0 million, respectively, on the NDT assets still held as of March 31, 2018 and net unrealized losses of $0.4 million and net unrealized gains of $1.4 million, respectively, on the Rabbi trust assets still held as of March 31, 2018 Some of our investments in the NDT are measured at NAV and do not have readily determinable fair values. These investments are either with investment companies or companies that follow accounting guidance consistent with investment companies. In certain situations, these investments may have redemption restrictions. The following table provides additional information on these investments.
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Price Risk We use various types of fuel, including coal, natural gas, uranium and diesel to operate our plants and also purchase power to meet customer demand. Our prices and condensed consolidated financial results are exposed to market risks from commodity price changes for electricity and other energy-related products as well as from interest rates. Volatility in these markets impacts our costs of purchased power, costs of fuel for our generating plants and our participation in energy markets. We strive to manage our customers’ and our exposure to market risks through regulatory, operating and financing activities and, when we deem appropriate, we economically hedge a portion of these risks through the use of derivative financial instruments for non-trading purposes. Interest Rate Risk We have entered into numerous fixed and variable rate debt obligations. We manage our interest rate risk related to these debt obligations by limiting our exposure to variable interest rate debt and diversifying maturity dates. We may also use other financial derivative instruments such as entering into treasury yield hedge transactions and interest rate swaps. |
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- Definition Financial And Derivative Instruments And Investments [Text Block] No definition available.
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- Definition Financial And Derivative Instruments and Investments[Abstract] No definition available.
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Taxes |
3 Months Ended |
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Mar. 31, 2018 | |
| Income Tax Disclosure [Abstract] | |
| Taxes | TAXES We recorded income tax expense of $9.2 million with an effective income tax rate of 13% for the three months ended March 31, 2018, and income tax expense of $20.9 million with an effective income tax rate of 25% for the same period of 2017. The decrease in the effective income tax rate for the three months ended March 31, 2018, was due primarily to the TCJA, which was signed into law in December 2017 and decreased the federal corporate income tax rate from 35% to 21%. As of March 31, 2018, and December 31, 2017, our unrecognized income tax benefits totaled $1.7 million. We do not expect significant changes in our unrecognized income tax benefits in the next 12 months. As of March 31, 2018, and December 31, 2017, we had no amounts and $0.1 million, respectively, accrued for interest related to our unrecognized income tax benefits. We accrued no penalties at either March 31, 2018, or December 31, 2017. As of March 31, 2018, and December 31, 2017, we had recorded $0.5 million and $0.4 million, respectively, for probable assessments of taxes other than income taxes. |
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- Definition The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Pension and Post-Retirement Benefit Plans |
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| Retirement Benefits [Abstract] | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Pension And Post-Retirement Benefit Plans | PENSION AND POST-RETIREMENT BENEFIT PLANS The following table summarizes the net periodic costs for our pension and post-retirement benefit plans prior to the effects of capitalization.
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During the three months ended March 31, 2018 and 2017, we contributed $12.5 million and $7.0 million, respectively, to the Westar Energy pension trust. |
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- Definition The entire disclosure for pension and other postretirement benefits. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Wolf Creek Pension and Post-Retirement Benefit Plans |
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| Wolf Creek Pension And Post-Retirement Benefit Plans | WOLF CREEK PENSION AND POST-RETIREMENT BENEFIT PLANS As a co-owner of Wolf Creek, KGE is indirectly responsible for 47% of the liabilities and expenses associated with the Wolf Creek pension and post-retirement benefit plans. The following table summarizes the net periodic costs for KGE’s 47% share of the Wolf Creek pension and post-retirement benefit plans prior to the effects of capitalization.
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During the three months ended March 31, 2018 and 2017, we did not fund Wolf Creek’s pension plan. |
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- References No definition available.
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- Definition Includes disclosure of the entity's share of an affiliate's pension and other post-retirement benefits. No definition available.
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Commitments And Contingencies |
3 Months Ended |
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Mar. 31, 2018 | |
| Commitments and Contingencies Disclosure [Abstract] | |
| Commitments And Contingencies | COMMITMENTS AND CONTINGENCIES Environmental Matters Set forth below are descriptions of contingencies related to environmental matters that may impact us or our financial results. Our assessment of these contingencies, which are based on federal and state statutes and regulations, and regulatory agency and judicial interpretations and actions, has evolved over time. There are a variety of final and proposed laws and regulations that could have a material adverse effect on our operations and condensed consolidated financial results. Due in part to the complex nature of environmental laws and regulations, we are unable to assess the impact of potential changes that may develop with respect to the environmental contingencies described below. Cross-State Air Pollution Update Rule In September 2016, the Environmental Protection Agency (EPA) finalized the Cross-State Air Pollution Update Rule. The final rule addresses interstate transport of nitrogen oxides emissions in 22 states including Kansas, Missouri and Oklahoma during the ozone season and the impact from the formation of ozone on downwind states with respect to the 2008 ozone National Ambient Air Quality Standards (NAAQS). Starting with the 2017 ozone season, the final rule revised the existing ozone season allowance budgets for Missouri and Oklahoma and established an ozone season budget for Kansas. Various states and others are challenging the rule in the U.S. Court of Appeals for the D.C. Circuit but the rule remains in effect. We do not believe this rule will have a material impact on our operations and condensed consolidated financial results. National Ambient Air Quality Standards Under the CAA, the EPA sets NAAQS for certain emissions known as the “criteria pollutants” considered harmful to public health and the environment, including two classes of particulate matter (PM), ozone, nitrogen dioxide (NO2) (a precursor to ozone), carbon monoxide and sulfur dioxide (SO2), which result from fossil fuel combustion. Areas meeting the NAAQS are designated attainment areas while those that do not meet the NAAQS are considered nonattainment areas. Each state must develop a plan to bring nonattainment areas into compliance with the NAAQS. NAAQS must be reviewed by the EPA at five-year intervals. In October 2015, the EPA strengthened the ozone NAAQS by lowering the standards from 75 ppb to 70 ppb. In September 2016, the Kansas Department of Health & Environment (KDHE) recommended to the EPA that they designate eight counties in the state of Kansas as in attainment with the standard, and each remaining county in Kansas as attainment/unclassifiable. In November 2017, the EPA designated all counties in the State of Kansas as attainment/unclassifiable. We do not believe this will have a material impact on our condensed consolidated financial results. In December 2012, the EPA strengthened an existing NAAQS for one class of PM. In December 2014, the EPA designated the entire state of Kansas as attainment/unclassifiable with the standard. We do not believe this will have a material impact on our operations or condensed consolidated financial results. In 2010, the EPA revised the NAAQS for SO2. In March 2015, a federal court approved a consent decree between the EPA and environmental groups. The decree includes specific SO2 emissions criteria for certain electric generating plants that, if met, required the EPA to promulgate attainment/nonattainment designations for areas surrounding these plants. Tecumseh Energy Center is our only generating station that meets these criteria. In June 2016, the EPA accepted the State of Kansas recommendation to designate the areas surrounding the facility as unclassifiable. In addition, in January 2017, KDHE formally recommended to the EPA a 2,000 ton per year limit for Tecumseh Energy Center Unit 7 in order to satisfy the requirements of the 1-hour SO2 Data Requirements Rule that governs the next round of the designations. Also in January 2017, KDHE recommended the EPA change the designation of the area surrounding the facility from unclassifiable to attainment/unclassifiable. In August 2017, the EPA indicated they would address this area redesignation request in a separate action. By agreeing to the 2,000 ton per year limitation, no further characterization of the area surrounding the plant is required. We continue to communicate with our regulatory agencies regarding these standards and evaluate what impact the revised NAAQS could have on our operations and condensed consolidated financial results. If areas surrounding our facilities are designated in the future as nonattainment and/or we are required to install additional equipment to control emissions at our facilities, it could have a material impact on our operations and condensed consolidated financial results. Greenhouse Gases Burning coal and other fossil fuels releases carbon dioxide (CO2) and other gases referred to as GHG. Various regulations under the federal CAA limit CO2 and other GHG emissions, and other measures are being imposed or offered by individual states, municipalities and regional agreements with the goal of reducing GHG emissions. In October 2015, the EPA published a rule establishing new source performance standards (NSPS) for GHGs that limit CO2 emissions for new, modified and reconstructed coal and natural gas fueled electric generating units to various levels per Megawatt hour (MWh) depending on various characteristics of the units. Legal challenges to the GHG NSPS have been filed in the D.C. Circuit by various states and industry members. Also in October 2015, the EPA published a rule establishing guidelines for states to regulate CO2 emissions from existing power plants. The standards for existing plants are known as the Clean Power Plan (CPP). Under the CPP, interim emissions performance rates must be achieved beginning in 2022 and final emissions performance rates must be achieved by 2030. Legal challenges to the CPP were filed by groups of states and industry members, including us, in the D.C. Circuit. The CPP was stayed by the Supreme Court in February 2016 and, accordingly, is not currently being implemented by the states. In April 2017, the EPA published in the Federal Register a notice of withdrawal of the proposed CPP federal plan, proposed model trading rules and proposed Clean Energy Incentive Program design details. Also in April 2017, the EPA published a notice in the Federal Register that it was initiating administrative reviews of the CPP and the GHG NSPS. In October 2017, the EPA issued a proposed rule to repeal the CPP. The proposed rule indicates the CPP exceeds EPA’s authority and the EPA has not determined whether they will issue a replacement rule. The EPA is soliciting comments on the legal interpretations contained in this rulemaking. Comments were due in April 2018. In December 2017, the EPA issued an advance notice of proposed rulemaking. This proposed rulemaking was issued by the EPA because it is considering the possibility of changing certain aspects of the CPP and the EPA is soliciting feedback on specific areas that could be changed. Comments on these proposed areas of change were due to the EPA in February 2018. Due to the future uncertainty of the CPP, we cannot determine the impact on our operations or condensed consolidated financial results, but we believe the cost to comply with the CPP, should it be upheld and implemented in its current or a substantially similar form, could be material. Water We discharge some of the water used in our operations. This water may contain substances deemed to be pollutants. Revised rules governing such discharges from coal-fired power plants were issued in November 2015. The final rule establishes effluent limitations guidelines (ELG) and standards for wastewater discharges, including limits on the amount of toxic metals and other pollutants that can be discharged. Implementation timelines for these requirements vary from 2019 to 2023. In April 2017, the EPA announced it is reconsidering the ELG rule and court challenges have been placed in abeyance pending the EPA’s review. In September 2017, the EPA finalized a rule to postpone the compliance dates for the new, more stringent, effluent limitations and pretreatment standards for bottom ash transport water and flue gas desulfurization wastewater. These compliance dates have been postponed for two years while the EPA completes its administrative reconsideration of the ELG rule. We are evaluating the final rule and related developments and cannot predict the resulting impact on our operations or condensed consolidated financial results, but believe costs to comply could be material if the rule is implemented in its current or substantially similar form. In October 2014, the EPA’s final standards for cooling intake structures at power plants to protect aquatic life took effect. The standards, based on Section 316(b) of the federal Clean Water Act (CWA), require subject facilities to choose among seven best available technology options to reduce fish impingement. In addition, some facilities must conduct studies to assist permitting authorities to determine whether and what site-specific controls, if any, would be required to reduce entrainment of aquatic organisms. Our current analysis indicates this rule will not have a significant impact on our coal plants that employ cooling towers or cooling lakes that can be classified as closed cycle cooling. We do not expect the impact from this rule to be material. In June 2015, the EPA along with the U.S. Army Corps of Engineers issued a final rule, effective August 2015, defining the Waters of the United States (WOTUS) for purposes of the CWA. This rulemaking has the potential to impact all programs under the CWA. Expansion of regulated waterways is possible under the rule depending on regulating authority interpretation, which could impact several permitting programs. Various states and others have filed lawsuits challenging the WOTUS rule. In February 2018, the EPA and the U.S. Corps of Engineers finalized a rule adding an applicability date to the 2015 rule, which makes the implementation date of the rule February 2020. In July 2017, the EPA and the U.S. Army Corps of Engineers published in the Federal Register a proposed rule that would, if implemented, reinstate the definition of WOTUS that existed prior to the June 2015 expansion of the definition. Final action on the proposed rule is expected in 2018. We are currently evaluating the WOTUS rule and related developments. We do not believe the rule, if upheld and implemented in its current or substantially similar form, will have a material impact on our operations or condensed consolidated financial results. Regulation of Coal Combustion Residuals In the course of operating our coal generation plants, we produce coal combustion residuals (CCRs), including fly ash, gypsum and bottom ash. We recycle some of our ash production, principally by selling to the aggregate industry. The EPA published a rule to regulate CCRs in April 2015, which we believe will require additional CCR handling, processing and storage equipment and closure of certain ash disposal ponds. Impacts to operations will be dependent on the development of groundwater monitoring of CCR units being completed in 2017 and 2018. The Water Infrastructure Improvements for the Nation Act allows states to achieve delegated authority for CCR rules from the EPA. This has the potential to impact compliance options. Electric generation industry participants requested and the EPA has granted a request to reconsider portions of the final CCR regulation. In March 2018, the EPA proposed the Phase I CCR Remand Rule in order to modify portions of the 2015 rulemaking. This rule, should it become final, could introduce additional flexibility in CCR compliance. We have recorded an ARO for our current estimate for closure of ash disposal ponds but we may be required to record additional AROs in the future due to changes in existing CCR regulations, changes in interpretation of existing CCR regulations or changes in the timing or cost to close ash disposal ponds. If additional AROs are necessary, we believe the impact on our operations or condensed consolidated financial results could be material. Storage of Spent Nuclear Fuel Under the Nuclear Waste Policy Act of 1982, the Department of Energy (DOE) is responsible for the permanent disposal of spent nuclear fuel. In 2010, the DOE filed a motion with the NRC to withdraw its then pending application to construct a national repository for the disposal of spent nuclear fuel and high-level radioactive waste at Yucca Mountain, Nevada. An NRC board denied the DOE’s motion to withdraw its application and the DOE appealed that decision to the full NRC. In 2011, the NRC issued an evenly split decision on the appeal and also ordered the licensing board to close out its work on the DOE’s application by the end of 2011 due to a lack of funding. These agency actions prompted the states of Washington and South Carolina, and a county in South Carolina, to file a lawsuit in a federal Court of Appeals asking the court to compel the NRC to resume its license review and to issue a decision on the license application. In August 2013, the court ordered the NRC to resume its review of the DOE’s application. The NRC has not yet issued its decision. Wolf Creek has elected to build a dry cask storage facility to expand its existing on-site spent nuclear fuel storage, which is expected to provide additional capacity prior to 2025. Wolf Creek has finalized a settlement agreement through 2019 with the DOE for reimbursement of costs to construct this facility that would not have otherwise been incurred had the DOE begun accepting spent nuclear fuel. As a co-owner of Wolf Creek, in 2017 we received $0.8 million of the settlement representing reimbursement of costs incurred through 2015 for project planning, and in March 2018 we received $0.5 million for costs incurred between January 2016 and June 2017. We expect the majority of the remaining cost to construct the dry cask storage facility that would not have otherwise been incurred will be reimbursed by the DOE. We cannot predict when, or if, an off-site storage site or alternative disposal site will be available to receive Wolf Creek’s spent nuclear fuel and will continue to monitor this activity. TCJA Refund Liability In January 2018, the KCC issued an order to investigate the effect of the TCJA on regulated utilities and directed Kansas utilities to record a liability for the difference between the cost of service as approved in its most recent rate review and the cost of service that would have resulted had the provision for federal corporate income taxes been based upon the rate approved in the TCJA. We believe it is probable that we will be required to return these amounts to customers. We also believe it is probable that we will be required to return amounts to our transmission customers. See Note 5, “Rate Matters and Regulation,” for additional information. |
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- References No definition available.
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- Definition The entire disclosure for commitments and contingencies. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Legal Proceedings |
3 Months Ended |
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Mar. 31, 2018 | |
| Legal Proceedings [Abstract] | |
| Legal Proceedings | LEGAL PROCEEDINGS We and our subsidiaries are involved in various legal, environmental and regulatory proceedings. We believe that adequate provisions have been made and accordingly believe that the ultimate disposition of such matters will not have a material effect on our condensed consolidated financial results. See Notes 5 and 10, “Rate Matters and Regulation” and “Commitments and Contingencies,” for additional information. Pending Merger Following the announcement of the original merger agreement in May 2016, two putative class action petitions (which were consolidated and superseded by a consolidated class action petition) and one putative derivative petition challenging the original merger were filed in the District Court of Shawnee County, Kansas. In September 2016, the plaintiffs in both actions agreed in principle to dismiss the actions in exchange for our agreement to make supplemental disclosures to shareholders in connection with the original merger agreement and grant waivers of the prohibition on requesting a waiver of the standstill provisions in the confidentiality and standstill agreements executed by the bidders that participated in a sale process that was conducted as part of the original merger agreement. As described below, after the announcement of the revised merger agreement, the plaintiffs in the consolidated putative class action moved to amend their petition, and the plaintiff in the putative derivative case refiled his petition. The consolidated putative class action petition, originally filed July 25, 2016, is captioned In re Westar Energy, Inc. Stockholder Litigation, Case No. 2016-CV-000457. This petition named as defendants Westar Energy, the members of our board of directors and Great Plains Energy. On September 25, 2017, the lead plaintiff filed a motion for leave to amend her class action petition and attached an amended petition. The petition as amended now includes an additional plaintiff. The petition challenges the revised proposed merger and alleges a claim of breach of fiduciary duty against our board of directors and a claim of aiding and abetting that alleged breach against us and Great Plains Energy. The lawsuit seeks injunctive relief declaring the action maintainable as a class action and certifying that the plaintiffs are the class representatives; preliminarily and permanently enjoining the defendants from closing the merger unless we implement a procedure to obtain a merger agreement providing fair and reasonable terms and consideration to the plaintiffs and the class; rescinding the merger agreement or granting the plaintiffs and the class rescissory damages; directing our board of directors to account to the plaintiffs and the class for damages suffered as a result of the alleged breach of fiduciary duty; awarding the plaintiffs reasonable costs and disbursements of the action, including reasonable attorneys’ fees and expert fees; and granting other equitable relief as the court deems proper. The petition alleges inadequacies in our joint proxy statement concerning the revised proposed transaction and the degree to which our board of directors solicited or considered offers from prior bidders after the proposed original merger was denied by the KCC, and claims that the consideration our stockholders stand to receive in connection with the revised proposed transaction is unfair. Plaintiffs have added two new defendants, Monarch Energy Holding, Inc. and King Energy, Inc., whom they allege aided and abetted our board of directors in breaching their fiduciary duties. On October 18, 2017, the putative derivative petition, captioned Braunstein v. Chandler et al., Case No. 2017-CV-000692, was re-filed in the District Court of Shawnee County, Kansas. This putative derivative action names as defendants the members of our board of directors, Great Plains Energy, and subsidiaries of Great Plains Energy, with Westar Energy named as a nominal defendant. The petition asserts that the members of our board of directors breached their fiduciary duties to our shareholders in connection with actions taken after the KCC rejected the proposed original merger. It also asserts that Great Plains Energy and subsidiaries of Great Plains Energy aided and abetted such breaches of fiduciary duties. The petition alleges, among other things, that the members of our board of directors failed to obtain the best possible price for our shareholders because of a flawed process that discouraged third parties from submitting potentially superior proposals, and that members of our board of directors committed waste by not collecting termination fees that may have been payable following the KCC’s rejection of the original merger agreement. The petition seeks, among other remedies, an order enjoining the merger on the terms proposed and directing that the director defendants exercise their fiduciary duties to obtain a transaction, which is in the best interests of us and our shareholders, a declaration that the proposed merger was entered into in breach of the fiduciary duties of the defendants and is therefore unlawful and unenforceable, rescission of the merger agreement if consummated, the imposition of a constructive trust in favor of the plaintiff, on behalf of us, upon any benefits improperly received by the named defendants as a result of their wrongful conduct, and an award for costs, including attorneys’ fees and experts’ fees. In addition, on September 21, 2017, a putative class action lawsuit was filed in the United States District Court for the District of Kansas, captioned David Pill v. Westar Energy, Inc. et al, Civil Action No. 17-4086. The federal class action complaint challenges the merger and alleges violations of sections 14(a) and 20(a) of the Securities Exchange Act of 1934, as amended (Exchange Act). The complaint seeks an order declaring that the action is maintainable as a class action and certifying that the plaintiff is the class representative; preliminarily and permanently enjoining defendants from consummating the mergers or, if consummated, setting them aside and awarding rescissory damages; directing the defendants to file a registration statement on Form S-4 that corrects alleged misstatements; directing our board of directors to account to plaintiff and the class for their damages; awarding reasonable costs and disbursements of the action, including reasonable attorneys’ fees and expert fees; and granting other further relief as the court deems proper. On October 6, 2017, another putative class action lawsuit was filed in the United States District Court for the District of Kansas, captioned Robert L. Reese v. Westar Energy, Inc. et al, Civil Action No. 2:17-cv-02584. This federal class action complaint challenges the proposed merger and alleges violations of sections 14(a) and 20(a) of the Exchange Act. The complaint seeks an order enjoining the board and other parties from proceeding with, consummating, or closing the merger or, if consummated, setting it aside and awarding rescissory damages; directing the board to disseminate a registration statement that corrects alleged misstatements and includes all material facts the plaintiff asserts are missing; declaring that the defendants violated sections 14(a) and 20(a) of the Exchange Act and Rule 14a-9; awarding reasonable costs and disbursements of the action, including reasonable attorneys’ fees and expert fees; and granting other equitable relief as the court deems proper. On November 16, 2017, the parties in each of the actions independently agreed to withdraw requests for injunctive relief and otherwise agreed in principle to dismissing the actions with prejudice and to providing releases, in exchange for the supplemental disclosures that we filed in a Form 8-K on November 16, 2017. These agreements do not constitute any admission by any of the defendants as to the merits of any claims. In the future, the parties will prepare and present to the court for approval Stipulations of Settlement that will, if accepted by the court, settle the actions in their entirety. The outcome of litigation is inherently uncertain. The defense or settlement of any lawsuit or claim that remains unresolved at the time the merger closes may adversely affect the combined company’s business, financial condition or results of operation. |
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- Definition LEGAL PROCEEDINGS [Abstract] No definition available.
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- Definition Open legal proceedings in the normal course of business, including product liability and other litigation and contingencies. No definition available.
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Variable Interest Entities |
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| Variable Interest Entities | VARIABLE INTEREST ENTITY In determining the primary beneficiary of a VIE, we assess the entity’s purpose and design, including the nature of the entity’s activities and the risks that the entity was designed to create and pass through to its variable interest holders. A reporting enterprise is deemed to be the primary beneficiary of a VIE if it has (a) the power to direct the activities of the VIE that most significantly impact the VIE’s economic performance and (b) the obligation to absorb losses or right to receive benefits from the VIE that could potentially be significant to the VIE. The primary beneficiary of a VIE is required to consolidate the VIE. The trust holding our 50% interest in La Cygne unit 2 is a VIE of which we are the primary beneficiary. We assess all entities with which we become involved to determine whether such entities are VIEs and, if so, whether or not we are the primary beneficiary of the entity. We also continuously assess whether we are the primary beneficiary of the VIE with which we are involved. Prospective changes in facts and circumstances may cause us to reconsider our determination as it relates to the identification of the primary beneficiary. 50% Interest in La Cygne Unit 2 Under an agreement that expires in September 2029, KGE entered into a sale-leaseback transaction with a trust under which the trust purchased KGE’s 50% interest in La Cygne unit 2 and subsequently leased it back to KGE. The trust was financed with an equity contribution from an owner participant and debt issued by the trust. The trust was created specifically to purchase the 50% interest in La Cygne unit 2 and lease it back to KGE, and does not hold any other assets. We meet the requirements to be considered the primary beneficiary of the trust. In determining the primary beneficiary of the trust, we concluded that the activities of the trust that most significantly impact its economic performance and that we have the power to direct include (1) the operation and maintenance of the 50% interest in La Cygne unit 2 and (2) our ability to exercise a purchase option at the end of the agreement at the lesser of fair value or a fixed amount. We have the potential to receive benefits from the trust that could potentially be significant if the fair value of the 50% interest in La Cygne unit 2 at the end of the agreement is greater than the fixed amount. Financial Statement Impact We have recorded the following assets and liabilities on our condensed consolidated balance sheets related to the VIE described above.
_______________ (a) Included in accrued interest on our condensed consolidated balance sheets. All of the liabilities noted in the table above relate to the purchase of the property, plant and equipment. The assets of the VIE can be used only to settle obligations of the VIE and the VIE’s debt holders have no recourse to our general credit. We have not provided financial or other support to the VIE and are not required to provide such support. We did not record any gain or loss upon initial consolidation of the VIE. |
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- Definition Schedule Of Variable Interest Entities [Abstract] No definition available.
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- Definition Variable Interest Entities Disclosure [Text Block] No definition available.
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Summary Of Significant Accounting Policies (Policy) |
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| Trade and Other Accounts Receivable, Policy [Policy Text Block] | Allowance for Doubtful Accounts We determine our allowance for doubtful accounts based on the age of our receivables. We charge receivables off when they are deemed uncollectible, which is based on a number of factors including specific facts surrounding an account and management’s judgment. For the three months ended March 31, 2018 and 2017, we recorded bad debt expense related to contracts with customers of $4.0 million and $3.2 million, respectively. |
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| Revenue Recognition, Policy [Policy Text Block] | Revenue Recognition Revenue is recognized primarily at the time we deliver electricity or provide transmission service to customers. The time of delivery of electricity is generally when our obligation to provide service is satisfied. Sales tax and franchise fees that we collect concurrent with revenue-producing activities are excluded from revenue. For more information on revenue recognition, see Note 4, “Revenue.” We determine the amount of electricity delivered to customers through systematic monthly readings of customer meters. At the end of each month, we estimate how much electricity we have delivered since the prior meter reading and record the corresponding unbilled revenue. Our unbilled revenue estimate is affected by factors including energy demand, weather, line losses and changes in the composition of customer classes. We recorded estimated unbilled revenue of $68.2 million and $76.7 million as of March 31, 2018, and December 31, 2017, respectively. |
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| New Accounting Pronouncements, Policy [Policy Text Block] | New Accounting Pronouncements We prepare our condensed consolidated financial statements in accordance with GAAP for the United States of America. To address current issues in accounting, the Financial Accounting Standards Board (FASB) and the Securities and Exchange Commission (SEC) issued the following new accounting guidance that may affect our accounting and/or disclosure. Compensation - Retirement Benefits In March 2017, the FASB issued Accounting Standard Update (ASU) No. 2017-07, which requires employers to disaggregate the service cost component from other components of net periodic benefit costs and to disclose the amounts of net periodic benefit costs that are included in each income statement line item. The standard requires employers to report the service cost component in the same line item as other compensation costs and to report the other components of net periodic benefit costs (which include interest costs, expected return on plan assets, amortization of prior service cost or credits and actuarial gains and losses) separately and outside a subtotal of operating income. Of the components of net periodic benefit cost, only the service cost component will be eligible for capitalization as property, plant and equipment, which is applied prospectively. The other components of net periodic benefit costs that are no longer eligible for capitalization as property, plant and equipment will be recorded as a regulatory asset. The guidance changing the presentation in the statements of income is applied on a retrospective basis. The guidance permits and we elected upon adoption to use a practical expedient that allows us to use the amounts disclosed in Note 8, “Pension and Post-Retirement Benefit Plans,” for applying the retrospective presentation of the 2017 condensed consolidated statement of income. As a result, we retrospectively decreased operating, maintenance, and administrative expense by $5.0 million and increased other expense by $5.0 million for the three months ended March 31, 2017. The new standard is effective for annual periods beginning after December 15, 2017. We adopted the guidance for the Westar Energy pension and post-retirement benefit plans as of January 1, 2018, without a material impact on our condensed consolidated financial statements. Statement of Cash Flows In August 2016, the FASB issued ASU No. 2016-15, which clarifies how certain cash receipts and cash payments are presented and classified in the statement of cash flows. Among other clarifications, the guidance requires that cash proceeds received from the settlement of corporate-owned life insurance (COLI) policies be classified as cash inflows from investing activities and that cash payments for premiums on COLI policies may be classified as cash outflows for investing activities, operating activities or a combination of both. Retrospective application is required. We adopted the guidance effective January 1, 2018, which resulted in retrospective reclassification of cash proceeds of $1.3 million from the settlement of COLI policies from cash inflows from operating activities to cash inflows from investing activities for the three months ended March 31, 2017. In addition, cash payments of $0.9 million for premiums on COLI policies were reclassified from cash outflows used in operating activities to cash outflows used in investing activities for the same period. In November 2016, the FASB issued ASU No. 2016-18, which requires that statement of cash flows explain the change for the period of restricted cash and restricted cash equivalents along with cash and cash equivalents. The guidance requires a retrospective transition method and is effective for fiscal years beginning after December 15, 2017. We adopted the guidance effective January 1, 2018. As a result, we adjusted amounts previously reported for cash and cash equivalents to include restricted cash which resulted in an increase to beginning and ending cash, cash equivalents and restricted cash of $0.1 million for the three months ended March 31, 2017. Leases In February 2016, the FASB issued ASU No. 2016-02, which requires a lessee to recognize right-of-use assets and lease liabilities, initially measured at present value of the lease payments, on its balance sheet for leases with terms longer than 12 months. Leases are to be classified as either financing or operating leases, with that classification affecting the pattern of expense recognition in the income statement. Accounting for leases by lessors is largely unchanged. The criteria used to determine lease classification will remain substantially the same, but will be more subjective under the new guidance. The guidance is effective for fiscal years beginning after December 15, 2018, with early adoption permitted. The guidance requires a modified retrospective approach for all leases existing at the earliest period presented, or entered into by the date of initial adoption, with certain practical expedients permitted. In 2016, we started evaluating our current leases to assess the initial impact on our consolidated financial results. We continue to evaluate the guidance and believe application of the guidance will result in an increase to our assets and liabilities on our consolidated balance sheet, with minimal impact to our consolidated statement of income. We also continue to monitor unresolved industry issues, including renewables and power purchase agreements, and will analyze the related impact. The standard permits an entity to elect a practical expedient for existing or expired contracts to forgo reassessing leases to determine whether each is in scope of the new standard and to forgo reassessing lease classification. We expect to elect this practical expedient upon implementation. Financial Instruments In January 2016, the FASB issued ASU No. 2016-01, which generally requires equity investments to be measured at fair value with changes in fair value recognized in net income. Under the new standard, equity securities are no longer to be classified as available-for-sale or trading securities. The guidance requires a modified retrospective transition method. This guidance is effective for fiscal years beginning after December 15, 2017; accordingly, we adopted the new standard on January 1, 2018, without a material impact on our condensed consolidated financial statements. Revenue Recognition In May 2014, the FASB issued ASU No. 2014-09, which addresses revenue from contracts with customers. Subsequent ASUs have been released providing modifications and clarifications to ASU No. 2014-09. The objective of the new guidance is to establish principles to report useful information to users of financial statements about the nature, amount, timing and uncertainty of revenue from contracts with customers. Under the new standard, an entity must identify the performance obligations in a contract, determine the transaction price and allocate the price to specific performance obligations to recognize the revenue when the obligation is completed. This guidance is effective for fiscal years beginning after December 15, 2017; accordingly, we adopted the new standard on January 1, 2018. The standard permits the use of either the retrospective application or modified retrospective method. We elected to use the modified retrospective method, which requires a cumulative-effect adjustment to be recorded on the balance sheet as of the beginning of 2018, if applicable, as if the standard had always been in effect. Adoption of the standard did not have a material impact to our condensed consolidated financial statements and, as a result, we recorded no cumulative effect of initially applying the standard. For more information on revenue recognition, see Note 4, “Revenue.” |
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| Principles Of Consolidation | Principles of Consolidation We prepare our unaudited condensed consolidated financial statements in accordance with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, certain information and footnote disclosures normally included in financial statements presented in accordance with generally accepted accounting principles (GAAP) for the United States of America have been condensed or omitted. Our condensed consolidated financial statements include all operating divisions, majority owned subsidiaries and a variable interest entity (VIE) of which we maintain a controlling interest or are the primary beneficiary reported as a single reportable segment. Undivided interests in jointly-owned generation facilities are included on a proportionate basis. Intercompany accounts and transactions have been eliminated in consolidation. In our opinion, all adjustments, consisting of normal recurring adjustments considered necessary for a fair presentation of the condensed consolidated financial statements, have been included. |
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| Use Of Management's Estimates | Use of Management’s Estimates When we prepare our condensed consolidated financial statements, we are required to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenues and expenses, and related disclosure of contingent assets and liabilities at the date of our condensed consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. We evaluate our estimates on an ongoing basis, including those related to depreciation, unbilled revenue, valuation of investments, forecasted fuel costs included in our retail energy cost adjustment billed to customers, income taxes, pension and post-retirement benefits, our asset retirement obligations (AROs) including the decommissioning of Wolf Creek, environmental issues, VIEs, contingencies and litigation. Actual results may differ from those estimates under different assumptions or conditions. The results of operations for the three months ended March 31, 2018, are not necessarily indicative of the results to be expected for the full year. |
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| Fuel Inventory And Supplies | Fuel Inventory and Supplies We state fuel inventory and supplies at average cost. |
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| Allowance For Funds Used During Construction | Allowance for Funds Used During Construction Allowance for funds used during construction (AFUDC) represents the allowed cost of capital used to finance utility construction activity. We compute AFUDC by applying a composite rate to qualified construction work in progress. We credit other income (for equity funds) and interest expense (for borrowed funds) for the amount of AFUDC capitalized as construction cost |
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| Earnings Per Share | Earnings Per Share We have participating securities in the form of unvested restricted share units (RSUs) with nonforfeitable rights to dividend equivalents that receive dividends on an equal basis with dividends declared on common shares. As a result, we apply the two-class method of computing basic and diluted earnings per share (EPS). To compute basic EPS, we divide the earnings allocated to common stock by the weighted average number of common shares outstanding. Diluted EPS includes the effect of issuable common shares resulting from our RSUs with forfeitable rights to dividend equivalents. We compute the dilutive effect of potential issuances of common shares using the treasury stock method. |
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| Supplemental Cash Flow Information | Supplemental Cash Flow Information
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- References No definition available.
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- Definition Disclosure of accounting policy for AFUDC (for example, component of PPE, credit to income statement), information regarding the inclusion in rates (only capitalized if its inclusion in rates is probable) and description of AFUDC (for example, represents the cost of capital used during construction). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The entire disclosure for supplemental cash flow activities, including cash, noncash, and part noncash transactions, for the period. Noncash is defined as information about all investing and financing activities of an enterprise during a period that affect recognized assets or liabilities but that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Disclosure of accounting policy regarding (1) the principles it follows in consolidating or combining the separate financial statements, including the principles followed in determining the inclusion or exclusion of subsidiaries or other entities in the consolidated or combined financial statements and (2) its treatment of interests (for example, common stock, a partnership interest or other means of exerting influence) in other entities, for example consolidation or use of the equity or cost methods of accounting. The accounting policy may also address the accounting treatment for intercompany accounts and transactions, noncontrolling interest, and the income statement treatment in consolidation for issuances of stock by a subsidiary. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Disclosure of accounting policy for computing basic and diluted earnings or loss per share for each class of common stock and participating security. Addresses all significant policy factors, including any antidilutive items that have been excluded from the computation and takes into account stock dividends, splits and reverse splits that occur after the balance sheet date of the latest reporting period but before the issuance of the financial statements. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Disclosure of inventory accounting policy for inventory classes, including, but not limited to, basis for determining inventory amounts, methods by which amounts are added and removed from inventory classes, loss recognition on impairment of inventories, and situations in which inventories are stated above cost. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Disclosure of accounting policy pertaining to new accounting pronouncements that may impact the entity's financial reporting. Includes, but is not limited to, quantification of the expected or actual impact. No definition available.
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- Definition Disclosure of accounting policy for revenue recognition. If the entity has different policies for different types of revenue transactions, the policy for each material type of transaction is generally disclosed. If a sales transaction has multiple element arrangements (for example, delivery of multiple products, services or the rights to use assets) the disclosure may indicate the accounting policy for each unit of accounting as well as how units of accounting are determined and valued. The disclosure may encompass important judgment as to appropriateness of principles related to recognition of revenue. The disclosure also may indicate the entity's treatment of any unearned or deferred revenue that arises from the transaction. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Disclosure of accounting policy for trade and other accounts receivables. This disclosure may include the basis at which such receivables are carried in the entity's statements of financial position (for example, net realizable value), how the entity determines the level of its allowance for doubtful accounts, when impairments, charge-offs or recoveries are recognized, and the entity's income recognition policies for such receivables, including its treatment of related fees and costs, its treatment of premiums, discounts or unearned income, when accrual of interest is discontinued, how the entity records payments received on nonaccrual receivables and its policy for resuming accrual of interest on such receivables. If the enterprise holds a large number of similar loans, disclosure may include the accounting policy for the anticipation of prepayments and significant assumptions underlying prepayment estimates for amortization of premiums, discounts, and nonrefundable fees and costs. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Disclosure of accounting policy for the use of estimates in the preparation of financial statements in conformity with generally accepted accounting principles. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Summary Of Significant Accounting Policies (Tables) |
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| Accounting Policies [Abstract] | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Schedule of Utility Inventory | Following are the balances for fuel inventory and supplies stated separately.
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| Allowance For Funds Used During Construction | on the accompanying condensed consolidated statements of income as follows:
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| Reconciliation Of Basic And Diluted EPS | The following table reconciles our basic and diluted EPS from net income.
_______________ (a)We had no antidilutive securities for the three months ended March 31, 2018 and 2017. |
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| Supplemental Cash Flow Information |
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- Definition Tabular disclosure of supplemental cash flow information for the periods presented. No definition available.
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- Definition Tabular disclosure of an entity's basic and diluted earnings per share calculations, including a reconciliation of numerators and denominators of the basic and diluted per-share computations for income from continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Tabular disclosure of all information related to inventories for utilities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Tabular disclosure of an entity's allowance for funds used during construction. No definition available.
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Revenue (Tables) |
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| Revenue from Contract with Customer [Abstract] | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Revenue from External Customers by Products and Services [Table Text Block] | The following table categorizes our revenue by class of customer.
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- Definition Tabular disclosure of entity-wide revenues from external customers for each product or service or each group of similar products or services if the information is not provided as part of the reportable operating segment information. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Financial Instruments and Investments (Tables) |
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| Financial And Derivative Instruments and Investments [Abstract] | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Carrying Values And Fair Values Of Financial Instruments | The following table provides the carrying values and measured fair values of our fixed-rate debt.
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| Fair Value Of Assets And Liabilities | The following table provides the amounts and their corresponding level of hierarchy for our assets that are measured at fair value.
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| Investments In Financial Instruments | The following table provides additional information on these investments.
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- Definition Tabular disclosure of assets and liabilities, including [financial] instruments measured at fair value that are classified in stockholders' equity, if any, that are measured at fair value on a recurring basis. The disclosures contemplated herein include the fair value measurements at the reporting date by the level within the fair value hierarchy in which the fair value measurements in their entirety fall, segregating fair value measurements using quoted prices in active markets for identical assets (Level 1), significant other observable inputs (Level 2), and significant unobservable inputs (Level 3). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition This item represents the disclosure regarding the investments in certain entities that calculate net asset value per share that enables users to understand the nature and risks of the investments and whether the investments are probable of being sold at amounts different from net asset value per share. Such disclosure may include (1) the fair value of the investments in the major category, and a description of the significant investment strategies of the investee(s) in the major category; (2) for each major category of investment that includes investments that can never be redeemed with the investees, but the reporting entity receives distributions through the liquidation of the underlying assets of the investees, the reporting entity's estimate of the period of time over which the underlying assets are expected to be liquidated by the investees; (3) the amount of the entity's unfunded commitments related to investments in the major category; (4) a general description of the terms and conditions upon which the investor may redeem investments in the major category; (5) the circumstances in which an otherwise redeemable investment in the major category might not be redeemable; (6) for those otherwise redeemable investments that are restricted from redemption as of the reporting entity's measurement date, the entity's best estimate of when the restriction from redemption might lapse; if an estimate cannot be made, the entity shall disclose that fact and how long the restriction has been in effect; (7) any other significant restriction on the ability to sell investments in the major category at the measurement date; (8) total fair value of held for sale investments and any remaining actions required to complete the sale when the reporting entity determines that it is probable that it will sell the investments for an amount different from net asset value per share; and (9) disclosure of an entity's plans to sell and any remaining actions required to complete the sale when the entity intends to sell a group of investments, but the individual investments to be sold have not been identified. No definition available.
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- Definition Financial And Derivative Instruments and Investments[Abstract] No definition available.
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- Definition Schedule of Carrying Value and Fair Values of Financial Instruments. No definition available.
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Pension and Post-Retirement Benefit Plans (Tables) |
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| Retirement Benefits [Abstract] | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Schedule of Net Periodic Benefit Costs [Table Text Block] | The following table summarizes the net periodic costs for our pension and post-retirement benefit plans prior to the effects of capitalization.
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- References No definition available.
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- Definition Tabular disclosure of the components of net benefit costs for pension plans and/or other employee benefit plans including service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) recognized due to settlements or curtailments. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Wolf Creek Pension and Post-Retirement Benefit Plans (Tables) |
3 Months Ended | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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| Wolf Creek Pension And Post-Retirement Benefit Plans [Line Items] | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Schedule of Net Periodic Benefit Costs [Table Text Block] | The following table summarizes the net periodic costs for our pension and post-retirement benefit plans prior to the effects of capitalization.
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| Wolf Creek [Member] | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Wolf Creek Pension And Post-Retirement Benefit Plans [Line Items] | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Schedule of Net Periodic Benefit Costs [Table Text Block] | The following table summarizes the net periodic costs for KGE’s 47% share of the Wolf Creek pension and post-retirement benefit plans prior to the effects of capitalization.
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- Definition Tabular disclosure of the components of net benefit costs for pension plans and/or other employee benefit plans including service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) recognized due to settlements or curtailments. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Wolf Creek Interim Pension And Post-Retirement Benefit Disclosure [Line Items] No definition available.
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- Details
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Variable Interest Entities (Tables) |
3 Months Ended | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Mar. 31, 2018 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Variable Interest Entities [Abstract] | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Assets And Liabilities of VIEs | We have recorded the following assets and liabilities on our condensed consolidated balance sheets related to the VIE described above.
_______________ (a) Included in accrued interest on our condensed consolidated balance sheets. |
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| X | ||||||||||
- Definition Tabular disclosure of the significant judgments and assumptions made in determining whether a variable interest (as defined) held by the entity requires the variable interest entity (VIE) (as defined) to be consolidated and (or) disclose information about its involvement with the VIE, individually or in aggregate (as applicable); the nature of restrictions, if any, on the consolidated VIE's assets and on the settlement of its liabilities reported by an entity in its statement of financial position, including the carrying amounts of such assets and liabilities; the nature of, and changes in, the risks associated with involvement in the VIE; how involvement with the VIE affects the entity's financial position, financial performance, and cash flows; the lack of recourse if creditors (or beneficial interest holders) of the consolidated VIE have no recourse to the general credit of the primary beneficiary (if applicable); the terms of arrangements, giving consideration to both explicit arrangements and implicit variable interests, if any, that could require the entity to provide financial support to the VIE, including events or circumstances that could expose the entity to a loss; the methodology used by the entity for determining whether or not it is the primary beneficiary of the variable interest entity; the significant factors considered and judgments made in determining that the power to direct the activities of a VIE that most significantly impact the VIE's economic performance are shared (as defined); the carrying amounts and classification of assets and liabilities of the VIE included in the statement of financial position; the entity's maximum exposure to loss, if any, as a result of its involvement with the VIE, including how the maximum exposure is determined and significant sources of the entity's exposure to the VIE; a comparison of the carrying amounts of the assets and liabilities and the entity's maximum exposure to loss; information about any liquidity arrangements, guarantees, and (or) other commitments by third parties that may affect the fair value or risk of the entity's variable interest in the VIE; whether or not the entity has provided financial support or other support (explicitly or implicitly) to the VIE that it was not previously contractually required to provide or whether the entity intends to provide that support, including the type and amount of the support and the primary reasons for providing the support; and supplemental information the entity determines necessary to provide. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Schedule Of Variable Interest Entities [Abstract] No definition available.
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Description Of Business (Details) |
3 Months Ended |
|---|---|
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Mar. 31, 2018
Customers
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| Organization, Consolidation and Presentation of Financial Statements [Abstract] | |
| Number of customers in Kansas | 710,000 |
| X | ||||||||||
- References No definition available.
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| X | ||||||||||
- Definition Number Of Customers Getting Electric Generation, Transmission And Distribution Services No definition available.
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Summary Of Significant Accounting Policies (Fuel Inventory And Supplies) (Details) - USD ($) $ in Thousands |
Mar. 31, 2018 |
Dec. 31, 2017 |
|---|---|---|
| Public Utilities, Inventory [Line Items] | ||
| Total | $ 286,831 | $ 293,562 |
| Fuel Inventory [Member] | ||
| Public Utilities, Inventory [Line Items] | ||
| Public Utilities Inventory | 89,125 | 94,039 |
| Supplies [Member] | ||
| Public Utilities, Inventory [Line Items] | ||
| Public Utilities Inventory | $ 197,706 | $ 199,523 |
| X | ||||||||||
- Definition Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition The period end amount for a type of inventory held by the utility in a schedule of inventories. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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Summary Of Significant Accounting Policies (Allowance For Funds Used During Construction) (Details) - USD ($) $ in Thousands |
3 Months Ended | |
|---|---|---|
Mar. 31, 2018 |
Mar. 31, 2017 |
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| Accounting Policies [Abstract] | ||
| Borrowed funds | $ (1,403) | $ (1,853) |
| Equity funds | 1,097 | 775 |
| Total | $ 2,500 | $ 2,628 |
| Average AFUDC rates | 3.60% | 2.20% |
| X | ||||||||||
- References No definition available.
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| X | ||||||||||
- Definition Total increase in earnings in the period representing the cost of equity (based on assumed rate of return) and/or borrowed funds (based on interest rate) used to finance construction of regulated assets, which is expected to be recovered through rate adjustments. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition The component of the allowance for funds used during construction during the period based on an assumed rate of return on equity funds used in financing the construction of regulated assets. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount capitalized of allowance for funds used during construction. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Effective rate, including composite rate, of cost of financing additions to qualifying regulated assets, commonly called allowance for funds used during construction. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Summary Of Significant Accounting Policies (Reconciliation Of Basic And Diluted EPS) (Details) - USD ($) $ / shares in Units, $ in Thousands |
3 Months Ended | |
|---|---|---|
Mar. 31, 2018 |
Mar. 31, 2017 |
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| Accounting Policies [Abstract] | ||
| Net Income Allocated to RSUs | $ 104 | $ 108 |
| Net income allocated to common stock | $ 60,381 | $ 59,553 |
| Weighted Average Number of Shares Outstanding , Basic | 142,635,490 | 142,436,622 |
| RSUs | 16,090 | 258,984 |
| Weighted average equivalent common shares outstanding - diluted | 142,651,580 | 142,695,606 |
| Earnings Per Share, Basic | $ 0.42 | $ 0.42 |
| Earnings Per Share, Diluted | $ 0.42 | $ 0.42 |
| Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] | ||
| Antidilutive securities | 0 | 0 |
| X | ||||||||||
- References No definition available.
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| X | ||||||||||
- Definition Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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| X | ||||||||||
- Definition The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Number of additional shares included in diluted EPS for potentially dilutive effect of nonvested equity-based payment award containing forfeitable rights to dividends or dividend equivalents, whether paid or unpaid. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of earnings (loss) distributed and earnings (loss) allocated to participating securities for the diluted earnings (loss) per share or per unit calculation under the two-class method. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Earnings distributed and earnings allocated to common stock under the two-class method. No definition available.
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Summary Of Significant Accounting Policies (Supplemental Cash Flow Information) (Details) - USD ($) $ in Thousands |
3 Months Ended | |
|---|---|---|
Mar. 31, 2018 |
Mar. 31, 2017 |
|
| Cash Paid For (Received From) | ||
| Interest on financing activities | $ 33,043 | $ 35,644 |
| Income Taxes Paid, Net | (231) | (13,000) |
| Noncash Investing and Financing Transactions | ||
| Property, plant and equipment | 29,790 | 97,196 |
| Issuance of common stock for reinvested dividends and compensation plans | 149 | 2,349 |
| Assets acquired through capital leases | 48 | 293 |
| Variable Interest Entity, Primary Beneficiary [Member] | ||
| Cash Paid For (Received From) | ||
| Interest on financing activities | $ 1,319 | $ 1,696 |
| X | ||||||||||
- Definition The increase during the period in capital lease obligations due to entering into new capital leases. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of cash paid for interest. Includes, but is not limited to, payment to settle zero-coupon bond attributable to accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- References No definition available.
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| X | ||||||||||
- Definition The amount of fixed assets that an Entity acquires in a noncash (or part noncash) acquisition. Noncash is defined as information about all investing and financing activities of an enterprise during a period that affect recognized assets or liabilities but that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition The fair value of stock issued in noncash financing activities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- References No definition available.
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| X | ||||||||||
- Details
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Summary Of Significant Accounting Policies Summary Of Significant Accounting Policies (Details) - USD ($) $ in Thousands |
3 Months Ended | ||
|---|---|---|---|
Mar. 31, 2018 |
Mar. 31, 2017 |
Dec. 31, 2017 |
|
| New Accounting Pronouncements or Change in Accounting Principle [Line Items] | |||
| Unbilled Receivables, Current | $ 68,200 | $ 76,700 | |
| Allowance for Doubtful Accounts Receivable | $ 4,000 | $ 3,200 | |
| New Accounting Pronouncements, Policy [Policy Text Block] | New Accounting Pronouncements We prepare our condensed consolidated financial statements in accordance with GAAP for the United States of America. To address current issues in accounting, the Financial Accounting Standards Board (FASB) and the Securities and Exchange Commission (SEC) issued the following new accounting guidance that may affect our accounting and/or disclosure. Compensation - Retirement Benefits In March 2017, the FASB issued Accounting Standard Update (ASU) No. 2017-07, which requires employers to disaggregate the service cost component from other components of net periodic benefit costs and to disclose the amounts of net periodic benefit costs that are included in each income statement line item. The standard requires employers to report the service cost component in the same line item as other compensation costs and to report the other components of net periodic benefit costs (which include interest costs, expected return on plan assets, amortization of prior service cost or credits and actuarial gains and losses) separately and outside a subtotal of operating income. Of the components of net periodic benefit cost, only the service cost component will be eligible for capitalization as property, plant and equipment, which is applied prospectively. The other components of net periodic benefit costs that are no longer eligible for capitalization as property, plant and equipment will be recorded as a regulatory asset. The guidance changing the presentation in the statements of income is applied on a retrospective basis. The guidance permits and we elected upon adoption to use a practical expedient that allows us to use the amounts disclosed in Note 8, “Pension and Post-Retirement Benefit Plans,” for applying the retrospective presentation of the 2017 condensed consolidated statement of income. As a result, we retrospectively decreased operating, maintenance, and administrative expense by $5.0 million and increased other expense by $5.0 million for the three months ended March 31, 2017. The new standard is effective for annual periods beginning after December 15, 2017. We adopted the guidance for the Westar Energy pension and post-retirement benefit plans as of January 1, 2018, without a material impact on our condensed consolidated financial statements. Statement of Cash Flows In August 2016, the FASB issued ASU No. 2016-15, which clarifies how certain cash receipts and cash payments are presented and classified in the statement of cash flows. Among other clarifications, the guidance requires that cash proceeds received from the settlement of corporate-owned life insurance (COLI) policies be classified as cash inflows from investing activities and that cash payments for premiums on COLI policies may be classified as cash outflows for investing activities, operating activities or a combination of both. Retrospective application is required. We adopted the guidance effective January 1, 2018, which resulted in retrospective reclassification of cash proceeds of $1.3 million from the settlement of COLI policies from cash inflows from operating activities to cash inflows from investing activities for the three months ended March 31, 2017. In addition, cash payments of $0.9 million for premiums on COLI policies were reclassified from cash outflows used in operating activities to cash outflows used in investing activities for the same period. In November 2016, the FASB issued ASU No. 2016-18, which requires that statement of cash flows explain the change for the period of restricted cash and restricted cash equivalents along with cash and cash equivalents. The guidance requires a retrospective transition method and is effective for fiscal years beginning after December 15, 2017. We adopted the guidance effective January 1, 2018. As a result, we adjusted amounts previously reported for cash and cash equivalents to include restricted cash which resulted in an increase to beginning and ending cash, cash equivalents and restricted cash of $0.1 million for the three months ended March 31, 2017. Leases In February 2016, the FASB issued ASU No. 2016-02, which requires a lessee to recognize right-of-use assets and lease liabilities, initially measured at present value of the lease payments, on its balance sheet for leases with terms longer than 12 months. Leases are to be classified as either financing or operating leases, with that classification affecting the pattern of expense recognition in the income statement. Accounting for leases by lessors is largely unchanged. The criteria used to determine lease classification will remain substantially the same, but will be more subjective under the new guidance. The guidance is effective for fiscal years beginning after December 15, 2018, with early adoption permitted. The guidance requires a modified retrospective approach for all leases existing at the earliest period presented, or entered into by the date of initial adoption, with certain practical expedients permitted. In 2016, we started evaluating our current leases to assess the initial impact on our consolidated financial results. We continue to evaluate the guidance and believe application of the guidance will result in an increase to our assets and liabilities on our consolidated balance sheet, with minimal impact to our consolidated statement of income. We also continue to monitor unresolved industry issues, including renewables and power purchase agreements, and will analyze the related impact. The standard permits an entity to elect a practical expedient for existing or expired contracts to forgo reassessing leases to determine whether each is in scope of the new standard and to forgo reassessing lease classification. We expect to elect this practical expedient upon implementation. Financial Instruments In January 2016, the FASB issued ASU No. 2016-01, which generally requires equity investments to be measured at fair value with changes in fair value recognized in net income. Under the new standard, equity securities are no longer to be classified as available-for-sale or trading securities. The guidance requires a modified retrospective transition method. This guidance is effective for fiscal years beginning after December 15, 2017; accordingly, we adopted the new standard on January 1, 2018, without a material impact on our condensed consolidated financial statements. Revenue Recognition In May 2014, the FASB issued ASU No. 2014-09, which addresses revenue from contracts with customers. Subsequent ASUs have been released providing modifications and clarifications to ASU No. 2014-09. The objective of the new guidance is to establish principles to report useful information to users of financial statements about the nature, amount, timing and uncertainty of revenue from contracts with customers. Under the new standard, an entity must identify the performance obligations in a contract, determine the transaction price and allocate the price to specific performance obligations to recognize the revenue when the obligation is completed. This guidance is effective for fiscal years beginning after December 15, 2017; accordingly, we adopted the new standard on January 1, 2018. The standard permits the use of either the retrospective application or modified retrospective method. We elected to use the modified retrospective method, which requires a cumulative-effect adjustment to be recorded on the balance sheet as of the beginning of 2018, if applicable, as if the standard had always been in effect. Adoption of the standard did not have a material impact to our condensed consolidated financial statements and, as a result, we recorded no cumulative effect of initially applying the standard. For more information on revenue recognition, see Note 4, “Revenue.” |
||
| Operating, maintenance, and administrative | $ 139,993 | 135,319 | |
| Proceeds from investment in corporate-owned life insurance | 2,559 | 1,414 | |
| Investment in corporate-owned life insurance | $ 998 | 913 | |
| Accounting Standards Update 2017-07 [Member] | |||
| New Accounting Pronouncements or Change in Accounting Principle [Line Items] | |||
| Operating, maintenance, and administrative | 5,000 | ||
| Operating, maintenance, and administrative | 5,000 | ||
| Accounting Standards Update 2016-15 [Member] | |||
| New Accounting Pronouncements or Change in Accounting Principle [Line Items] | |||
| Proceeds from investment in corporate-owned life insurance | 1,300 | ||
| Investment in corporate-owned life insurance | 900 | ||
| Accounting Standards Update 2016-18 [Member] | |||
| New Accounting Pronouncements or Change in Accounting Principle [Line Items] | |||
| Increase (Decrease) in Restricted Cash and Investments | $ 100 | ||
| X | ||||||||||
- Definition For an unclassified balance sheet, a valuation allowance for receivables due a company that are expected to be uncollectible. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The net cash inflow or outflow during the period for the aggregate increase (decrease) associated with funds and investments that are not available for withdrawal or use (such as assets held in escrow or contractually limited as to use or disposition) and are associated with underlying transactions that are classified as investing activities. No definition available.
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- Definition The change in cash surrender or contract value during the period which adjusted the amount of premiums paid in determining the expense or income recognized under the contract for the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Disclosure of accounting policy pertaining to new accounting pronouncements that may impact the entity's financial reporting. Includes, but is not limited to, quantification of the expected or actual impact. No definition available.
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- Definition Amount of expense classified as other. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of cash inflow for proceeds from settlement of corporate-owned life insurance policy, classified as investing activities. Includes, but is not limited to, bank-owned life insurance policy. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount received for services rendered and products shipped, but not yet billed, for non-contractual agreements due within one year or the normal operating cycle, if longer. No definition available.
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- Definition Amount of operating expense for routine plant maintenance, repairs and operations of regulated operation. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Percentage of voting equity interests acquired at the acquisition date in the business combination. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Percentage of public utility's requested debt to capital, including debt and equity. No definition available.
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- Definition Business Acquisition, Dividend Restriction No definition available.
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- Definition Business Combination, Share Conversion Ratio Westar Energy No definition available.
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- Definition Merger Annual Bill Credits No definition available.
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- Definition Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Current regulatory liabilities generally represent obligations to make refunds to customers for various reasons including overpayment. No definition available.
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- Definition Amount of public utility's approved rate increase (decrease) by regulatory agency. No definition available.
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- Definition Amount of public utility's amended requested rate increase (decrease) with regulatory agency. No definition available.
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- Definition Amount of public utility's requested rate increase (decrease) with regulatory agency. No definition available.
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- Definition Percentage of public utility's requested return on equity. No definition available.
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- Definition Estimated Increase In Annual Retail Revenues For Transmission Costs No definition available.
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Financial Instruments and Investments (Carrying Values And Fair Values Of Financial Instruments) (Details) - USD ($) $ in Thousands |
Mar. 31, 2018 |
Dec. 31, 2017 |
|---|---|---|
| Fixed Rate Debt Member | ||
| Debt Instrument [Line Items] | ||
| Carrying Value | $ 3,605,000 | $ 3,605,000 |
| Fair Value | 3,759,785 | 3,888,620 |
| Fixed Rate Debt Of Variable Interest Entities Member | ||
| Debt Instrument [Line Items] | ||
| Carrying Value | 81,433 | 109,967 |
| Fair Value | $ 80,557 | $ 110,756 |
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- Definition Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The fair value of investments held in a trust fund to pay for the costs of decontaminating and decommissioning facilities, whether such amount is presented as a separate caption or as a parenthetical disclosure on the balance sheet. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Remaining period of a redemption restriction related to investments for which net asset value per share is calculated, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Financial And Derivative Instruments, Investments, Energy Marketing And Risk Management [Line Items] No definition available.
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- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The fair value of investments held in a trust fund to pay for the costs of decontaminating and decommissioning facilities, whether such amount is presented as a separate caption or as a parenthetical disclosure on the balance sheet. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition States the frequency (for example, annually, semi-annually, quarterly) with which the entity can redeem its investment, or portion thereof, for each of those certain investments for which net asset value per share is calculated (including by unit, membership interest, or other equity (ownership interest) unit measure) (alternative investments), by major category. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Notice period the entity is required to deliver before it can redeem an investment calculated using net asset value per share, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Includes, but is not limited to, investments calculated by per unit, per membership interest, other equity or ownership interest and alternative investments. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Remaining period of a redemption restriction related to investments for which net asset value per share is calculated, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The amount of unfunded commitments for which the entity is obligated, to those certain investments for which net asset value per share is calculated (including by unit, membership interest, or other equity (ownership interest) unit measure) (alternative investments). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of unrealized gain (loss) recognized in the income statement on unsold other securities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Financial And Derivative Instruments, Investments, Energy Marketing And Risk Management [Line Items] No definition available.
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Taxes Taxes (Narrative) (Details) - USD ($) |
3 Months Ended | 12 Months Ended | |
|---|---|---|---|
Mar. 31, 2018 |
Mar. 31, 2017 |
Dec. 31, 2017 |
|
| Income Tax Contingency [Line Items] | |||
| Income tax expense | $ 9,174,000 | $ 20,911,000 | |
| Effective income tax rate | 13.00% | 25.00% | |
| Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent | 21.00% | 35.00% | |
| Liability for unrecognized income tax benefits | $ 1,700,000 | $ 1,700,000 | |
| Interest on liability related to unrecognized income tax benefits | 0 | 100,000 | |
| Penalties accrued for unrecognized income tax benefits | 0 | 0 | |
| Accrual for taxes other than income taxes | $ 500,000 | $ 400,000 | |
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- Definition Carrying value as of the balance sheet date of obligations incurred and payable for real and property taxes. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Percentage of domestic federal statutory tax rate applicable to pretax income (loss). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of unrecognized tax benefits. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of statutory penalties accrued for a tax position claimed or expected to be claimed by the entity, in its tax return. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of interest expense accrued for an underpayment of income taxes. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Pension and Post-Retirement Benefit Plans (Net Periodic Costs And Pension Contributions) (Details) - USD ($) $ in Thousands |
3 Months Ended | ||||||
|---|---|---|---|---|---|---|---|
Mar. 31, 2018 |
Mar. 31, 2017 |
||||||
| Components of Net Periodic Cost (Benefit): | |||||||
| Payment for Pension Benefits | $ 12,500 | $ 7,000 | |||||
| Pension Benefits [Member] | |||||||
| Components of Net Periodic Cost (Benefit): | |||||||
| Service cost | 5,826 | 5,218 | |||||
| Interest cost | [1] | 10,207 | 10,621 | ||||
| Expected return on plan assets | [1] | (11,091) | (10,760) | ||||
| Prior service costs | [1] | 166 | 171 | ||||
| Actuarial loss, net | [1] | 6,485 | 5,489 | ||||
| Net periodic cost before regulatory adjustment | 11,593 | 10,739 | |||||
| Regulatory adjustment | [2] | 2,849 | 3,288 | ||||
| Net periodic cost | 14,442 | 14,027 | |||||
| Post-Retirement Benefits [Member] | |||||||
| Components of Net Periodic Cost (Benefit): | |||||||
| Service cost | 279 | 271 | |||||
| Interest cost | [1] | 1,183 | 1,314 | ||||
| Expected return on plan assets | [1] | (1,728) | (1,718) | ||||
| Prior service costs | [1] | 114 | 114 | ||||
| Actuarial loss, net | [1] | (135) | (195) | ||||
| Net periodic cost before regulatory adjustment | (287) | (214) | |||||
| Regulatory adjustment | [2] | (434) | (478) | ||||
| Net periodic cost | $ (721) | $ (692) | |||||
| |||||||
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- Definition Amount of gain (loss) recognized in net periodic benefit (cost) credit of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of prior service cost (credit) recognized in net periodic benefit cost (credit) of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of expected return (loss) recognized in net periodic benefit (cost) credit, calculated based on expected long-term rate of return and market-related value of plan assets of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of cost recognized for passage of time related to defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of net periodic benefit cost (credit) for defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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- Definition Amount of cost for actuarial present value of benefits attributed to service rendered by employee for defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of payment for pension benefits. Excludes other postretirement benefits. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The total amount of net periodic benefit cost for defined benefit plans for the period prior to regulatory adjustment. No definition available.
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- Definition Defined Benefit Plan Regulatory Adjustment No definition available.
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Wolf Creek Pension and Post-Retirement Benefit Plans Wolf Creek Pension and Post-Retirement Benefit Plans (Net Periodic Costs and Pension Contributions) (Details) - USD ($) $ in Thousands |
3 Months Ended | ||||||||
|---|---|---|---|---|---|---|---|---|---|
Mar. 31, 2018 |
Mar. 31, 2017 |
||||||||
| Components of Net Periodic Cost (Benefit): | |||||||||
| Payment for Pension Benefits | $ 12,500 | $ 7,000 | |||||||
| Wolf Creek [Member] | |||||||||
| Components of Net Periodic Cost (Benefit): | |||||||||
| Payment for Pension Benefits | $ 0 | 0 | |||||||
| KGE [Member] | |||||||||
| Subsidiary Interest in Defined Benefit Plans | 47.00% | ||||||||
| Pension Benefits [Member] | |||||||||
| Components of Net Periodic Cost (Benefit): | |||||||||
| Service cost | $ 5,826 | 5,218 | |||||||
| Interest cost | [1] | 10,207 | 10,621 | ||||||
| Expected return on plan assets | [1] | (11,091) | (10,760) | ||||||
| Prior service costs | [1] | 166 | 171 | ||||||
| Actuarial loss, net | [1] | 6,485 | 5,489 | ||||||
| Net periodic cost before regulatory adjustment | 11,593 | 10,739 | |||||||
| Regulatory adjustment | [2] | 2,849 | 3,288 | ||||||
| Net periodic cost | 14,442 | 14,027 | |||||||
| Pension Benefits [Member] | Wolf Creek [Member] | |||||||||
| Components of Net Periodic Cost (Benefit): | |||||||||
| Service cost | 2,220 | 1,950 | |||||||
| Interest cost | 2,478 | 2,475 | |||||||
| Expected return on plan assets | (2,891) | (2,643) | |||||||
| Prior service costs | 14 | 14 | |||||||
| Actuarial loss, net | 1,656 | 1,245 | |||||||
| Net periodic cost before regulatory adjustment | 3,477 | 3,041 | |||||||
| Regulatory adjustment | [3] | (49) | 247 | ||||||
| Net periodic cost | 3,428 | 3,288 | |||||||
| Post-Retirement Benefits [Member] | |||||||||
| Components of Net Periodic Cost (Benefit): | |||||||||
| Service cost | 279 | 271 | |||||||
| Interest cost | [1] | 1,183 | 1,314 | ||||||
| Expected return on plan assets | [1] | (1,728) | (1,718) | ||||||
| Prior service costs | [1] | 114 | 114 | ||||||
| Actuarial loss, net | [1] | (135) | (195) | ||||||
| Net periodic cost before regulatory adjustment | (287) | (214) | |||||||
| Regulatory adjustment | [2] | (434) | (478) | ||||||
| Net periodic cost | (721) | (692) | |||||||
| Post-Retirement Benefits [Member] | Wolf Creek [Member] | |||||||||
| Components of Net Periodic Cost (Benefit): | |||||||||
| Service cost | 36 | 37 | |||||||
| Interest cost | 61 | 70 | |||||||
| Expected return on plan assets | 0 | 0 | |||||||
| Prior service costs | 0 | 0 | |||||||
| Actuarial loss, net | (14) | (13) | |||||||
| Net periodic cost before regulatory adjustment | 83 | 94 | |||||||
| Regulatory adjustment | [3] | 0 | 0 | ||||||
| Net periodic cost | $ 83 | $ 94 | |||||||
| |||||||||
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- Definition Amount of gain (loss) recognized in net periodic benefit (cost) credit of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of prior service cost (credit) recognized in net periodic benefit cost (credit) of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of expected return (loss) recognized in net periodic benefit (cost) credit, calculated based on expected long-term rate of return and market-related value of plan assets of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of cost recognized for passage of time related to defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of net periodic benefit cost (credit) for defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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- Definition Amount of cost for actuarial present value of benefits attributed to service rendered by employee for defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of payment for pension benefits. Excludes other postretirement benefits. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The total amount of net periodic benefit cost for defined benefit plans for the period prior to regulatory adjustment. No definition available.
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- Definition Defined Benefit Plan Regulatory Adjustment No definition available.
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- Definition Subsidiary's interest in defined benefit plans. No definition available.
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- Details
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Commitments And Contingencies Commitments And Contingencies (Narrative) (Details) - USD ($) $ in Millions |
Mar. 01, 2018 |
Jun. 02, 2017 |
|---|---|---|
| Commitments and Contingencies Disclosure [Abstract] | ||
| Settlement Assets, Current | $ 0.5 | $ 0.8 |
| X | ||||||||||
- References No definition available.
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| X | ||||||||||
- Definition Cash received or short term receivables for unsettled money transfers, money orders, consumer payments, or business to business payments. Settlement assets include clearing and settling customers payments due to and from financial institutions and may include cash and cash equivalents. No definition available.
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Variable Interest Entities (Narrative) (Details) |
3 Months Ended |
|---|---|
|
Mar. 31, 2018
USD ($)
| |
| Variable Interest Entity [Line Items] | |
| Variable Interest Entity, Initial Consolidation, Gain (Loss) | $ 0 |
| La Cygne Generating Station [Member] | |
| Variable Interest Entity [Line Items] | |
| Variable interest entity percentage of asset held | 50.00% |
| Agreement expiration date | Sep. 01, 2029 |
| X | ||||||||||
- Definition Date which lease or group of leases is set to expire, in CCYY-MM-DD format. No definition available.
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- Definition The gain (loss) recognized on initial consolidation of a variable interest entity (VIE) when the VIE is not a business (as defined). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition The percentage of an asset held by a variable interest entity that is consolidated by the entity. No definition available.
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- Details
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Variable Interest Entities (Assets And Liabilities In Relation To VIEs) (Details) - USD ($) $ in Thousands |
Mar. 31, 2018 |
Dec. 31, 2017 |
|---|---|---|
| Variable Interest Entity [Line Items] | ||
| Property, plant and equipment, net | $ 9,589,164 | $ 9,553,755 |
| Accrued interest | 91,741 | 72,693 |
| Long-term debt, net | 3,688,257 | 3,687,555 |
| Variable Interest Entity, Primary Beneficiary [Member] | ||
| Variable Interest Entity [Line Items] | ||
| Property, plant and equipment, net | 174,500 | 176,279 |
| Current maturities of long-term debt | 30,337 | 28,534 |
| Accrued interest | 0 | 659 |
| Long-term debt, net | $ 51,096 | $ 81,433 |
| X | ||||||||||
- Definition Carrying value as of the balance sheet date of [accrued] interest payable on all forms of debt, including trade payables, that has been incurred and is unpaid. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Details
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| Label | Element | Value |
|---|---|---|
| Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents | us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents | $ 3,156,000 |
| Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents | us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents | 3,520,000 |
| Restricted Cash | us-gaap_RestrictedCash | 90,000 |
| Restricted Cash | us-gaap_RestrictedCash | $ 88,000 |
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- Definition Amount of cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage. Excludes amount for disposal group and discontinued operations. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of cash restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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