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RATE MATTERS AND REGULATION - Regulatory Matters Asset (Details) - USD ($) $ in Millions | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | ---
Regulatory Assets [Line Items] |  |
Regulatory Assets | $ 2,087.4 | $ 2,214.3
Less: current portion | (292.1) | (368.0)
Total noncurrent regulatory assets | 1,795.3 | 1,846.3
Pension and post-retirement costs |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 91.6 | 137.3
Regulatory asset representing differences between pension and post retirement costs for GAAP and for ratemaking | 91.3 |
Remaining Amounts of Regulatory Assets for which No Return on Investment During Recovery Period is Provided | 82.1 |
Debt reacquisition costs |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 81.2 | 87.7
Debt fair value adjustment |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 87.0 | 92.1
Asset retirement obligations fair value adjustment |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 120.7 | 119.4
Depreciation |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 168.7 | 159.1
Cost of removal |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 372.3 | 346.8
Asset retirement obligations |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 152.9 | 127.5
Analog meter unrecovered investment |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 8.3 | 12.6
Treasury yield hedges |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 18.1 | 19.2
Iatan No. 1 and common facilities |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 5.9 | 6.2
Iatan No. 2 construction accounting costs |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 23.4 | 24.0
Property taxes |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 56.0 | 51.4
Disallowed plant costs |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 13.5 | 13.9
La Cygne environmental costs |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 8.8 | 10.0
Deferred customer programs |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 20.3 | 14.3
Remaining Amounts of Regulatory Assets for which No Return on Investment During Recovery Period is Provided | 13.6 |
Fuel recovery mechanisms |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | $ 101.3 | 188.5
Regulatory Asset, Amortization Period | 1 year |
February 2021 winter weather event |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | $ 403.5 | 430.9
Solar rebates |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 9.9 | 15.6
Transmission delivery charge |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 2.0 | 1.5
Wolf Creek outage |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 8.4 | 22.8
Pension and other post-retirement benefit non-service costs |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 85.8 | 75.3
Retired generation facility, approved |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 138.2 | 146.3
Merger transition costs |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 23.1 | 28.1
Other regulatory liabilities |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 86.5 | 83.8
Evergy Kansas Central |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 632.9 | 711.9
Less: current portion | (127.7) | (121.9)
Total noncurrent regulatory assets | 505.2 | 590.0
Evergy Kansas Central | Pension and post-retirement costs |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 29.7 | 54.9
Regulatory asset representing differences between pension and post retirement costs for GAAP and for ratemaking | (34.3) |
Remaining Amounts of Regulatory Assets for which No Return on Investment During Recovery Period is Provided | 29.7 |
Evergy Kansas Central | Debt reacquisition costs |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 75.3 | 80.9
Evergy Kansas Central | Debt fair value adjustment |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 0.0 | 0.0
Evergy Kansas Central | Asset retirement obligations fair value adjustment |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 0.0 | 0.0
Evergy Kansas Central | Depreciation |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 44.6 | 47.2
Evergy Kansas Central | Cost of removal |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 165.6 | 158.2
Evergy Kansas Central | Asset retirement obligations |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 65.9 | 54.5
Evergy Kansas Central | Analog meter unrecovered investment |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 8.3 | 12.6
Evergy Kansas Central | Treasury yield hedges |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 18.1 | 19.2
Evergy Kansas Central | Iatan No. 1 and common facilities |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 0.0 | 0.0
Evergy Kansas Central | Iatan No. 2 construction accounting costs |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 0.0 | 0.0
Evergy Kansas Central | Property taxes |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 28.3 | 33.0
Evergy Kansas Central | Disallowed plant costs |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 13.5 | 13.9
Evergy Kansas Central | La Cygne environmental costs |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 6.8 | 7.9
Evergy Kansas Central | Deferred customer programs |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 6.7 | 6.5
Evergy Kansas Central | Fuel recovery mechanisms |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 0.0 | 0.0
Evergy Kansas Central | February 2021 winter weather event |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 79.7 | 121.9
Evergy Kansas Central | Solar rebates |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 0.0 | 0.0
Evergy Kansas Central | Transmission delivery charge |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 0.9 | 0.0
Evergy Kansas Central | Wolf Creek outage |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 4.2 | 11.4
Evergy Kansas Central | Pension and other post-retirement benefit non-service costs |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 32.0 | 24.8
Evergy Kansas Central | Retired generation facility, approved |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 0.0 | 0.0
Evergy Kansas Central | Merger transition costs |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 11.0 | 13.3
Evergy Kansas Central | Other regulatory liabilities |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 42.3 | 51.7
Evergy Metro |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 434.0 | 373.8
Less: current portion | (53.2) | (42.3)
Total noncurrent regulatory assets | 380.8 | 331.5
Evergy Metro | Pension and post-retirement costs |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 0.0 | 0.0
Regulatory asset representing differences between pension and post retirement costs for GAAP and for ratemaking | 65.3 |
Evergy Metro | Debt reacquisition costs |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 5.3 | 6.0
Evergy Metro | Debt fair value adjustment |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 0.0 | 0.0
Evergy Metro | Asset retirement obligations fair value adjustment |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 0.0 | 0.0
Evergy Metro | Depreciation |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 66.0 | 57.1
Evergy Metro | Cost of removal |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 168.2 | 140.6
Evergy Metro | Asset retirement obligations |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 64.0 | 53.4
Evergy Metro | Analog meter unrecovered investment |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 0.0 | 0.0
Evergy Metro | Treasury yield hedges |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 0.0 | 0.0
Evergy Metro | Iatan No. 1 and common facilities |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 2.5 | 2.6
Evergy Metro | Iatan No. 2 construction accounting costs |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 11.7 | 12.0
Evergy Metro | Property taxes |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 25.3 | 15.8
Evergy Metro | Disallowed plant costs |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 0.0 | 0.0
Evergy Metro | La Cygne environmental costs |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 2.0 | 2.1
Evergy Metro | Deferred customer programs |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 11.2 | 6.7
Remaining Amounts of Regulatory Assets for which No Return on Investment During Recovery Period is Provided | 11.2 |
Evergy Metro | Fuel recovery mechanisms |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 14.1 | 13.5
Evergy Metro | February 2021 winter weather event |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 0.0 | 0.0
Evergy Metro | Solar rebates |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 0.0 | 0.0
Evergy Metro | Transmission delivery charge |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 1.1 | 1.5
Evergy Metro | Wolf Creek outage |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 4.2 | 11.4
Evergy Metro | Pension and other post-retirement benefit non-service costs |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 34.2 | 30.7
Evergy Metro | Retired generation facility, approved |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 0.0 | 0.0
Evergy Metro | Merger transition costs |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | 8.6 | 10.5
Evergy Metro | Other regulatory liabilities |  |
Regulatory Assets [Line Items] |  |
Regulatory Assets | $ 15.6 | $ 9.9

X
- Definition Regulatory asset (liability) that represents the differences between pension and post-retirement costs under GAAP and pension and post-retirement costs for ratemaking that will be recovered or refunded in rates, as appropriate, over future periods. + References No definition available. + Details
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- Definition Amortization period for the recovery of regulatory asset, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 980 -SubTopic 340 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481878/980-340-50-1 + Details
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