Document And Entity Information - USD ($) |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2018 |
Feb. 15, 2019 |
Jun. 30, 2018 |
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| Entity information [Abstract] | |||
| Entity Registrant Name | EVERGY, INC. | ||
| Entity Central Index Key | 0001711269 | ||
| Current Fiscal Year End Date | --12-31 | ||
| Entity Filer Category | Large Accelerated Filer | ||
| Document Type | 10-K | ||
| Document Period End Date | Dec. 31, 2018 | ||
| Document Fiscal Year Focus | 2018 | ||
| Document Fiscal Period Focus | FY | ||
| Amendment Flag | false | ||
| Entity Common Stock, Shares Outstanding | 254,630,033 | ||
| Entity Well-known Seasoned Issuer | Yes | ||
| Entity Voluntary Filers | No | ||
| Entity Current Reporting Status | Yes | ||
| Entity Public Float | $ 15,236,578,926 | ||
| Entity Shell Company | false | ||
| Entity Emerging Growth Company | false | ||
| Entity Small Business | false |
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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 'Yes' or 'No' whether registrants (1) have filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that registrants were required to file such reports), and (2) have been subject to such filing requirements for the past 90 days. 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 Indicate if registrant meets the emerging growth company criteria. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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), (5) Smaller Reporting Accelerated Filer or (6) Smaller Reporting Company and Large 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. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition State aggregate market value of voting and non-voting common equity held by non-affiliates computed by reference to price at which the common equity was last sold, or average bid and asked price of such common equity, as of the last business day of registrant's most recently completed second fiscal quarter. The public float should be reported on the cover page of the registrants form 10K. 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 Indicate if company meets the shell company criteria: a company with no or nominal operations, and with no or nominal assets or assets consisting solely of cash and cash equivalents. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Indicates that the company is a smaller reporting company with both a public float and revenues of less than $75 million. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Indicate 'Yes' or 'No' if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act. No definition available.
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- Definition Indicate 'Yes' or 'No' if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Is used on Form Type: 10-K, 10-Q, 8-K, 20-F, 6-K, 10-K/A, 10-Q/A, 20-F/A, 6-K/A, N-CSR, N-Q, N-1A. No definition available.
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- Definition Entity information for DEI No definition available.
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- Definition Defined Benefit Pension Plans [Abstract] No definition available.
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- Definition Derivative Hedging Activity [Abstract] No definition available.
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- Definition Amount of operating expense for fuel and purchased power used by regulated operation No definition available.
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- Definition Cost incurred for SPP transmission costs No definition available.
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- Definition Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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- Definition Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income. Excludes changes in equity resulting from investments by owners and distributions to owners. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Total costs of sales and operating expenses for the period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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- Definition The current period expense charged against earnings on long-lived, physical assets not used in production, and which are not intended for resale, to allocate or recognize the cost of such assets over their useful lives; or to record the reduction in book value of an intangible asset over the benefit period of such asset; or to reflect consumption during the period of an asset that is not used in production. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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/disclosureRef
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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/exampleRef
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- Definition Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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/disclosureRef
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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/disclosureRef
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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://fasb.org/us-gaap/role/ref/legacyRef
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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/disclosureRef
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- Definition Amount of Net Income (Loss) attributable to noncontrolling interest. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The net result for the period of deducting operating expenses from operating revenues. No definition available.
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- Definition Amount, after tax, of gain (loss) for (increase) decrease in value of benefit obligation for change in actuarial assumptions and increase (decrease) in value of plan assets from experience different from that assumed of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of tax expense (benefit) for (increase) decrease in value of benefit obligation for change in actuarial assumptions and increase (decrease) in value of plan assets from experience different from that assumed of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount after tax and reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount after tax and reclassification adjustments of other comprehensive income (loss). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount after tax of other comprehensive income (loss) attributable to noncontrolling interests. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount, after tax and reclassification adjustment, of (increase) decrease in accumulated other comprehensive income for defined benefit plan. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount, before tax, of gain (loss) for (increase) decrease in value of benefit obligation for change in actuarial assumptions and increase (decrease) in value of plan assets from experience different from that assumed of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount after tax of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount before tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount after tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of tax expense (benefit), before reclassification adjustments, related to increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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- Definition Amount of expense related to nonoperating activities, classified as other. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of income related to nonoperating activities, classified as other. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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/disclosureRef
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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/disclosureRef
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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://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of operating expense for routine plant maintenance, repairs and operations of regulated operation. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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://fasb.org/us-gaap/role/ref/legacyRef
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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://fasb.org/us-gaap/role/ref/legacyRef
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- Details
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- References 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://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount for accounts payable to related parties. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of receivables arising from transactions with related parties due within one year or the normal operating cycle, if longer. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Current 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://fasb.org/us-gaap/role/ref/legacyRef
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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://fasb.org/us-gaap/role/ref/legacyRef
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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://fasb.org/us-gaap/role/ref/legacyRef
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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://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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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 after one year or beyond the normal operating cycle, if longer. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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://fasb.org/us-gaap/role/ref/legacyRef
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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://fasb.org/us-gaap/role/ref/legacyRef
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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://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Decommission fund to pay for the costs of decontaminating and decommissioning of facilities through collection of revenues derived from utility assessments and government appropriations. Decommission fund investment for the process whereby a power station, at the end of its economic life, is taken permanently out of service and its site made available for other purposes. In the case of a nuclear station this comprises three different states of clearance. Immediately after the final closure, radioactive material such as nuclear fuel and operational waste is removed and the buildings surrounding the reactor shield are dismantled and finally the reactor itself is dismantled. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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://fasb.org/us-gaap/role/ref/legacyRef
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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://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Carrying amount as of the balance sheet date of merchandise, goods, commodities, or supplies relating to a source of usable power held for future sale or future use in manufacturing or production process. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Carrying amount due within one year of the balance sheet date (or one operating cycle, if longer) from tax authorities as of the balance sheet date representing refunds of overpayments or recoveries based on agreed-upon resolutions of disputes. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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://fasb.org/us-gaap/role/ref/legacyRef
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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://fasb.org/us-gaap/role/ref/legacyRef
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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://fasb.org/us-gaap/role/ref/legacyRef
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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://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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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://fasb.org/us-gaap/role/ref/legacyRef
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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://fasb.org/us-gaap/role/ref/legacyRef
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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://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of noncurrent assets classified as other. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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://fasb.org/us-gaap/role/ref/legacyRef
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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://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of liability, recognized in statement of financial position, for defined benefit pension and other postretirement plans, classified as noncurrent. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The total amount due to the entity within one year of the balance sheet date (or one operating cycle, if longer) from outside sources, including trade accounts receivable, notes and loans receivable, as well as any other types of receivables, net of allowances established for the purpose of reducing such receivables to an amount that approximates their net realizable value. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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://fasb.org/us-gaap/role/ref/legacyRef
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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://fasb.org/us-gaap/role/ref/legacyRef
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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://fasb.org/us-gaap/role/ref/legacyRef
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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://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition The cumulative amount of the reporting entity's undistributed earnings or deficit. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Amount of borrowings from a bank classified as other, maturing within one year or operating cycle, if longer. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- 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://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- References No definition available.
|
| 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://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- 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://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Carrying amount of financial assets accounted for as secured borrowings recognized in the transferor's statement of financial position at the end of each period presented. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Carrying amount of liabilities associated with financial assets accounted for as secured borrowings recognized in the transferor's statement of financial position at the end of each period presented. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
Consolidated Balance Sheets (Parenthetical) - $ / shares |
Dec. 31, 2018 |
Dec. 31, 2017 |
|---|---|---|
| Shareholder's equity | ||
| Common stock - shares authorized (in shares) | 600,000,000 | 275,000,000 |
| Common stock - par value (in dollars per share) | $ 0 | $ 5 |
| Common stock - shares issued (in shares) | 255,326,252 | 142,094,275 |
| Westar Energy Inc [Member] | ||
| Shareholder's equity | ||
| Common stock - shares authorized (in shares) | 1,000 | 275,000,000 |
| Common stock - par value (in dollars per share) | $ 0.01 | $ 5 |
| Common stock - shares issued (in shares) | 1 | 142,094,275 |
| KCPL [Member] | ||
| Shareholder's equity | ||
| Common stock - shares authorized (in shares) | 1,000 | 1,000 |
| Common stock - shares issued (in shares) | 1 | 1 |
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Face amount or stated value per share of common stock. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition The maximum number of common shares permitted to be issued by an entity's charter and bylaws. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- 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://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Definition Amortization Of Corporate Owned Life Insurance No definition available.
|
| X | ||||||||||
- Definition Amortization Of Deferred Refueling Outage Costs No definition available.
|
| X | ||||||||||
- Definition The noncash expense, not otherwise specified in the taxonomy, charged against earnings in the period to allocate the cost of nuclear fuel over the operating cycle of the nuclear plant. No definition available.
|
| X | ||||||||||
- Definition Amortization Of Sale Leaseback Transaction No definition available.
|
| X | ||||||||||
- Definition The increase (decrease) during the reporting period in the amount due within one year (or one business cycle) from customers for the credit sale of goods and services where those amounts have been pledged as collateral. No definition available.
|
| X | ||||||||||
- Definition Increase (Decrease) In Energy Related Inventory No definition available.
|
| X | ||||||||||
- Definition Payments For Asset Retirement Obligations No definition available.
|
| X | ||||||||||
- Definition Proceeds From Borrowings Against Corporate Owned Life Insurance No definition available.
|
| X | ||||||||||
- Definition Proceeds From Issuance Of Collateralized Debt No definition available.
|
| X | ||||||||||
- Definition Proceeds From LTD VIE No definition available.
|
| X | ||||||||||
- Definition Purchase Of Corporate Owned Life Insurance No definition available.
|
| X | ||||||||||
- Definition Repayments Of Borrowings Against Corporate Owned Life Insurance No definition available.
|
| X | ||||||||||
- Definition Retirements of Long Term Debt Of VIEs No definition available.
|
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition The cash inflow associated with the acquisition of business during the period (for example, cash that was held by the acquired business). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| 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://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- 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://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Amount of increase (decrease) in cash, cash equivalents, and cash and cash equivalents restricted to withdrawal or usage; including effect from exchange rate change. 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://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Amount of deferred income tax expense (benefit) and income tax credits. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition The current period expense charged against earnings on long-lived, physical assets not used in production, and which are not intended for resale, to allocate or recognize the cost of such assets over their useful lives; or to record the reduction in book value of an intangible asset over the benefit period of such asset; or to reflect consumption during the period of an asset that is not used in production. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| 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://fasb.org/us-gaap/role/ref/legacyRef
|
| 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://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition The increase (decrease) during the reporting period of all taxes owed but not paid, including income, property and other taxes. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
|
| X | ||||||||||
- Definition The increase (decrease) during the reporting period in the capitalized 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. As a result of this capitalization, net income is increased. This element pertains to certain regulated industries, such as public utilities. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Amount of increase (decrease) in current liabilities classified as other. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
|
| X | ||||||||||
- Definition Amount of increase (decrease) in operating assets classified as other. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Amount of increase (decrease) in operating liabilities classified as other. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Amount of increase (decrease) in prepaid expenses, and assets classified as other. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Amount of cash inflow (outflow) from financing activities, including 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/disclosureRef
|
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Amount of cash inflow (outflow) from investing activities, including 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/disclosureRef
|
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Amount of cash inflow (outflow) from operating activities, including discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Amount of income (expense) included in net income that results in no cash inflow (outflow), classified as other. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Amount of cash (inflow) outflow from investing activities classified as other. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
|
| X | ||||||||||
- Definition The cash outflow to reacquire common stock during the period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Cash outflow in the form of capital distributions and dividends to common shareholders, preferred shareholders and noncontrolling interests. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| 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://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition The cash outflow for the purchase of investments that will be held in a decommissioning trust fund. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition The cash inflow from the sale of assets held in a decommissioning trust fund. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition The cash inflow provided by derivative instruments during the period, which are classified as investing activities, excluding those designated as hedging instruments. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
|
| X | ||||||||||
- Definition The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- 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://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Amount of cash inflow (outflow) from financing activities classified as other. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
|
| X | ||||||||||
- 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/2009/role/commonPracticeRef
|
| 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/disclosureRef
|
| 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://fasb.org/us-gaap/role/ref/legacyRef
|
| 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://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
Consolidated Statements of Cash Flows (Parenthetical) - USD ($) $ in Millions |
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
|---|---|---|---|---|
| Restricted cash | $ 0.0 | $ 0.1 | $ 0.1 | $ 0.1 |
| Westar Energy Inc [Member] | ||||
| Restricted cash | $ 0.0 | $ 0.1 | $ 0.1 | $ 0.1 |
| X | ||||||||||
- Definition Amount of cash and cash equivalents 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. 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://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Definition Stock Canceled During Period, Shares No definition available.
|
| X | ||||||||||
- Definition Stock Canceled During Period, Value No definition available.
|
| X | ||||||||||
- Definition Stock Issued During Period, Shares, Dividend Reinvestment Plan And Share-Based Compensation No definition available.
|
| X | ||||||||||
- Definition Stock Issued During Period, Value, Dividend Reinvestment Plan And Share-Based Compensation No definition available.
|
| 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.
|
| X | ||||||||||
- Definition Amount of increase to additional paid-in capital (APIC) from recognition of equity-based compensation. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption. No definition available.
|
| X | ||||||||||
- Definition Amount of paid and unpaid common stock dividends declared with the form of settlement in cash. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Amount of paid and unpaid cash, stock, and paid-in-kind (PIK) dividends declared and applicable to holders of share-based compensation, for example, but not limited to, non-vested shares, stock options, or restricted stock units. No definition available.
|
| X | ||||||||||
- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
|
| 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://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition The amount of the reduction or elimination during the period of a noncontrolling interest resulting from the parent's loss of control and deconsolidation of the entity in which one or more outside parties had a noncontrolling interest. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Amount after tax and reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Amount, after tax and reclassification adjustment, of (increase) decrease in accumulated other comprehensive income for defined benefit plan. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| 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/disclosureRef
|
| X | ||||||||||
- Definition Number of shares issued which are neither cancelled nor held in the treasury. No definition available.
|
| X | ||||||||||
- Definition Number of shares of stock issued during the period pursuant to acquisitions. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Number of new stock issued during the period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Number of shares issued during the period related to Restricted Stock Awards, net of any shares forfeited. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Value of stock issued pursuant to acquisitions during the period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| 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://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| 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://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition This element represents movements included in the statement of changes in stockholders' equity which are not separately disclosed or provided for elsewhere in the taxonomy. No definition available.
|
Consolidated Statements of Changes in Equity (Parenthetical) - $ / shares |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
|
| Dividends declared on common stock (in dollars per share) | $ 1.735 | $ 1.60 | $ 1.52 |
| X | ||||||||||
- Definition Aggregate dividends declared during the period for each share of common stock outstanding. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
Summary of Significant Accounting Policies Summary of Significant Accounting Policies |
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| Accounting Policies [Abstract] | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Significant Accounting Policies [Text Block] | 1. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Organization Evergy is a public utility holding company incorporated in 2017 and headquartered in Kansas City, Missouri. Evergy operates primarily through the following wholly-owned direct subsidiaries:
Westar Energy also owns a 50% interest in Prairie Wind Transmission, LLC (Prairie Wind), which is a joint venture between Westar Energy and affiliates of AEP and Berkshire Hathaway Energy Company. Prairie Wind owns a 108-mile, 345 kV double-circuit transmission line that provides transmission service in the Southwest Power Pool, Inc. (SPP). Westar Energy accounts for its investment in Prairie Wind under the equity method. Westar Energy and KGE conduct business in their respective service territories using the name Westar Energy. KCP&L and GMO conduct business in their respective service territories using the name KCP&L. Collectively, the Evergy Companies have approximately 14,500 MWs of owned generating capacity and renewable purchased power agreements and engage in the generation, transmission, distribution and sale of electricity to approximately 1.6 million customers in the states of Kansas and Missouri. Evergy was incorporated in 2017 as Monarch Energy Holding, Inc. (Monarch Energy), a wholly-owned subsidiary of Great Plains Energy Incorporated (Great Plains Energy). Prior to the closing of the merger transactions, Monarch Energy changed its name to Evergy and did not conduct any business activities other than those required for its formation and matters contemplated by the Amended and Restated Agreement and Plan of Merger, dated as of July 9, 2017, by and among Great Plains Energy, Westar Energy, Monarch Energy and King Energy, Inc. (King Energy), a wholly-owned subsidiary of Monarch Energy (Amended Merger Agreement). On June 4, 2018, in accordance with the Amended Merger Agreement, Great Plains Energy merged into Evergy, with Evergy surviving the merger and King Energy merged into Westar Energy, with Westar Energy surviving the merger. These merger transactions resulted in Evergy becoming the parent entity of Westar Energy and the direct subsidiaries of Great Plains Energy, including KCP&L and GMO. See Note 2 for additional information regarding the merger. Principles of Consolidation Westar Energy was determined to be the accounting acquirer in the merger and thus, the predecessor of Evergy. Therefore, Evergy's consolidated financial statements reflect the results of operations of Westar Energy for 2017 and 2016 and the financial position of Westar Energy as of December 31, 2017. Evergy had separate operations for the period beginning with the quarter ended June 30, 2018, and references to amounts for periods after the closing of the merger relate to Evergy. The results of Great Plains Energy's direct subsidiaries have been included in Evergy's results of operations from the date of the closing of the merger and thereafter. Westar Energy and KCP&L continue to be Securities and Exchange Commission (SEC) registrants. KCP&L has elected not to apply "push-down accounting" related to the merger, whereby the adjustments of assets and liabilities to fair value and the resulting goodwill would be recorded on the financial statements of the acquired subsidiary. These adjustments for KCP&L, as well as those related to the acquired assets and liabilities of Great Plains Energy and its other direct subsidiaries, are only reflected on Evergy's consolidated financial statements. Each of Evergy's, Westar Energy's and KCP&L's consolidated financial statements includes the accounts of their subsidiaries and variable interest entities (VIEs) of which they are the primary beneficiary. Undivided interests in jointly-owned generation facilities are included on a proportionate basis. Intercompany transactions have been eliminated. The Evergy Companies assess financial performance and allocate resources on a consolidated basis (i.e., operate in one segment). Certain changes in classification and corresponding reclassification of prior period data were made in Evergy's, Westar Energy's and KCP&L's consolidated balance sheets, statements of income and comprehensive income and statements of cash flows for comparative purposes. Evergy reflects the classifications of Westar Energy as the accounting acquirer in the merger. These reclassifications did not affect Evergy's, Westar Energy's or KCP&L's net income or Evergy's, Westar Energy's or KCP&L's cash flows from operations, investing or financing. Most significantly for Westar Energy's consolidated balance sheets as of December 31, 2017, was the reclassification of $50.2 million from accrued employee benefits (currently reported as pension and post-retirement liability) to other long-term liabilities. Most significantly for KCP&L's consolidated balance sheets, current regulatory assets and liabilities have been presented separately from the non-current portions in each respective consolidated balance sheet where recovery or refund is expected within the next 12 months. The table below summarizes KCP&L's reclassifications related to operating and investing activities for its consolidated statement of cash flows for 2017 and 2016.
(a)Previously reported within Note 3 to the consolidated financial statements of the Great Plains Energy and KCP&L combined 2017 and 2016 Annual Reports on Form 10-K. Use of Estimates The process of preparing financial statements in conformity with generally accepted accounting principles (GAAP) requires the use of estimates and assumptions that affect the reported amounts of certain types of assets, liabilities, revenues and expenses. Such estimates primarily relate to unsettled transactions and events as of the date of the financial statements. Accordingly, upon settlement, actual results may differ from estimated amounts. Cash and Cash Equivalents Cash equivalents consist of highly liquid investments with original maturities of three months or less at acquisition. Fuel Inventory and Supplies The Evergy Companies record fuel inventory and supplies at average cost. The following table separately states the balances for fuel inventory and supplies.
(a) KCP&L amounts are not included in consolidated Evergy at December 31, 2017. Property, Plant and Equipment The Evergy Companies record the value of property, plant and equipment, including that of variable interest entities (VIEs), at cost. For plant, cost includes contracted services, direct labor and materials, indirect charges for engineering and supervision and an allowance for funds used during construction (AFUDC). AFUDC represents the allowed cost of capital used to finance utility construction activity. AFUDC equity funds are included as a non-cash item in other income and AFUDC borrowed funds are a reduction of interest expense. AFUDC is computed by applying a composite rate to qualified construction work in progress. The rates used to compute gross AFUDC are compounded semi-annually. The amounts of the Evergy Companies' AFUDC for borrowed and equity funds are detailed in the following table.
(a)KCP&L amounts are only included in consolidated Evergy from the date of the closing of the merger, June 4, 2018 through December 31, 2018. The average rates used in the calculation of AFUDC are detailed in the following table.
When property units are retired or otherwise disposed, the original cost net of salvage is charged to accumulated depreciation. Repair of property and replacement of items not considered to be units of property are expensed as incurred, except for planned refueling and maintenance outages at Wolf Creek Generating Station (Wolf Creek). As authorized by regulators, the expense is deferred and amortized ratably over the period between planned outages incremental maintenance cost incurred for such outages. Depreciation and Amortization Depreciation and amortization of utility plant other than nuclear fuel is computed using the straight-line method over the estimated lives of depreciable property based on rates approved by state regulatory authorities. Annual depreciation rates average approximately 3%. Nuclear fuel is amortized to fuel expense based on the quantity of heat produced during the generation of electricity. See Note 7 for more details. The depreciable lives of Evergy's, Westar Energy's and KCP&L's property, plant and equipment are detailed in the following table.
Plant to be Retired, Net When the Evergy Companies retire utility plant, the original cost, net of salvage, is charged to accumulated depreciation. However, when it becomes probable an asset will be retired significantly in advance of its original expected useful life and in the near term, the cost of the asset and related accumulated depreciation is recognized as a separate asset and a probable abandonment. If the asset is still in service, the net amount is classified as plant to be retired, net on the consolidated balance sheets. If the asset is no longer in service, the net amount is classified as a regulatory asset on the consolidated balance sheets. The Evergy Companies must also assess the probability of full recovery of the remaining net book value of the abandonment. The net book value that may be retained as an asset on the balance sheet for the abandonment is dependent upon amounts that may be recovered through regulated rates, including any return. An impairment charge, if any, would equal the difference between the remaining net book value of the asset and the present value of the future revenues expected from the asset. In June 2017, GMO announced the expected retirement of certain older generating units, including GMO's Sibley No. 3 Unit, over the next several years. GMO determined that Sibley No. 3 Unit met the criteria to be considered probable of abandonment. GMO retired Sibley Station, including the No. 3 Unit, in November 2018. As of December 31, 2018, Evergy has classified the remaining Sibley No. 3 Unit net book value of $159.9 million as retired generation facilities within regulatory assets on its consolidated balance sheet. Evergy is currently allowed a full recovery of and a full return on Sibley No. 3 Unit in rates and has concluded that no impairment is required as of December 31, 2018. Nuclear Plant Decommissioning Costs Nuclear plant decommissioning cost estimates are based on either the immediate dismantlement method or the deferred dismantling method as determined by the KCC and MPSC and include the costs of decontamination, dismantlement and site restoration. Based on these cost estimates, Westar Energy and KCP&L contribute to a tax-qualified trust fund to be used to decommission Wolf Creek. Related liabilities for decommissioning are included on Evergy's, Westar Energy's and KCP&L's consolidated balance sheets in Asset Retirement Obligations (AROs). As a result of the authorized regulatory treatment and related regulatory accounting, differences between the decommissioning trust fund asset and the related ARO are recorded as a regulatory asset or liability. See Note 6 for discussion of AROs including those associated with nuclear plant decommissioning costs. Regulatory Accounting Accounting standards are applied that recognize the economic effects of rate regulation. Accordingly, regulatory assets and liabilities have been recorded when required by a regulatory order or based on regulatory precedent. See Note 5 for additional information concerning regulatory matters. Cash Surrender Value of Life Insurance Amounts related to corporate-owned life insurance (COLI) are recorded on the consolidated balance sheets in other long-terms assets and are detailed in the following table for Evergy. Substantially all of Evergy's COLI-related balances relate to Westar Energy's COLI activity.
Increases in cash surrender value and death benefits are recorded in other income in the Evergy Companies' consolidated statements of income and comprehensive income. Interest expense incurred on policy loans is offset against the policy income. Income from death benefits is highly variable from period to period. Fair Value of Financial Instruments The following methods and assumptions were used to estimate the fair value of the following financial instruments for which it was practicable to estimate that value. Nuclear decommissioning trust fund - The Evergy Companies' nuclear decommissioning trust fund assets are recorded at fair value based on quoted market prices of the investments held by the fund and/or valuation models. Pension plans - For financial reporting purposes, the market value of plan assets is the fair value. Revenue Recognition The Evergy Companies recognize revenue on the sale of electricity to customers over time as the service is provided in the amount they have the right to invoice. Revenues recorded include electric services provided but not yet billed by the Evergy Companies. Unbilled revenues are recorded for kWh usage in the period following the customers' billing cycle to the end of the month. This estimate is based on net system kWh usage less actual billed kWhs. The Evergy Companies' estimated unbilled kWhs are allocated and priced by regulatory jurisdiction across the rate classes based on actual billing rates. The Evergy Companies' unbilled revenue estimate is affected by factors including fluctuations in energy demand, weather, line losses and changes in the composition of customer classes. See Note 4 for the balance of unbilled receivables for each of Evergy, Westar Energy and KCP&L as of December 31, 2018 and 2017. The Evergy Companies also collect sales taxes and franchise fees from customers concurrent with revenue-producing activities that are levied by state and local governments. These items are excluded from revenue, and thus are not reflected on the consolidated statements of income and comprehensive income for Evergy, Westar Energy and KCP&L. See Note 3 for additional details regarding revenue recognition from sales of electricity by the Evergy Companies. Allowance for Doubtful Accounts The Evergy Companies determine their allowance for doubtful accounts based on the age of their receivables. Receivables are charged off when they are deemed uncollectible, which is based on a number of factors including specific facts surrounding an account and management's judgment. Property Gains and Losses Net gains and losses from the sale of assets and businesses and from asset impairments are recorded in operating expenses. Asset Impairments Long-lived assets and finite-lived intangible assets subject to amortization are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. If the sum of the undiscounted expected future cash flows from an asset to be held and used is less than the carrying value of the asset, an asset impairment must be recognized in the financial statements. The amount of impairment recognized is the excess of the carrying value of the asset over its fair value. Goodwill and indefinite lived intangible assets are tested for impairment annually and when an event occurs indicating the possibility that an impairment exists. The annual test must be performed at the same time each year. Evergy's first impairment test for the $2,338.9 million of goodwill from the Great Plains Energy and Westar Energy merger will be conducted on May 1, 2019. The goodwill impairment test consists of comparing the fair value of a reporting unit to its carrying amount, including goodwill, to identify potential impairment. In the event that the carrying amount exceeds the fair value of the reporting unit, an impairment loss is recognized for the difference between the carrying amount of the reporting unit and its fair value. Income Taxes Income taxes are accounted for using the asset/liability approach. Deferred tax assets and liabilities are determined based on the temporary differences between the financial reporting and tax bases of assets and liabilities, applying enacted statutory tax rates in effect for the year in which the differences are expected to reverse. Deferred tax assets are reduced by a valuation allowance when, in the opinion of management, it is more likely than not that some portion of the deferred tax assets will not be realized. The Evergy Companies recognize tax benefits based on a "more-likely-than-not" recognition threshold. In addition, the Evergy Companies recognize interest accrued related to unrecognized tax benefits in interest expense and penalties in operating expenses. Evergy files a consolidated federal income tax return as well as unitary and combined income tax returns in several state jurisdictions with Kansas and Missouri being the most significant. Income taxes for consolidated or combined subsidiaries are allocated to the subsidiaries based on separate company computations of income or loss. Westar Energy's and KCP&L's income tax provisions include taxes allocated based on their separate company's income or loss. The Evergy Companies have established a net regulatory liability for future refunds to be made to customers for the over-collection of income taxes in rates. Tax credits are recognized in the year generated except for certain Westar Energy, KCP&L and GMO investment tax credits that have been deferred and amortized over the remaining service lives of the related properties. Other Income (Expense), Net The table below shows the detail of other expense for each of the Evergy Companies.
(a)KCP&L amounts are only included in consolidated Evergy from the date of the closing of the merger, June 4, 2018 through December 31, 2018. Earnings Per Share To compute basic earnings per share (EPS), Evergy divides net income attributable to Evergy, Inc. by the weighted average number of common shares outstanding. Diluted EPS includes the effect of issuable common shares resulting from restricted share units (RSUs), performance shares and restricted stock. Evergy computes the dilutive effects of potential issuances of common shares using the treasury stock method. The following table reconciles Evergy's basic and diluted EPS.
There were no anti-dilutive securities excluded from the computation of diluted EPS for 2018, 2017 and 2016. Supplemental Cash Flow Information
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