PENSION PLANS AND POST-RETIREMENT BENEFITS - Fair Values of Assets (Details) - USD ($) $ in Millions | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 |
Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | $ 1,732.8 | $ 1,603.4 | $ 887 |
Post-Retirement Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 239.9 | 223.3 | 124.1 |
Evergy Kansas Central | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 842.1 | 804.6 | 887 |
Evergy Kansas Central | Pension Benefits | Level 1 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 515.2 | 522 | |
Evergy Kansas Central | Pension Benefits | Level 2 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Kansas Central | Pension Benefits | Level 3 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Kansas Central | Pension Benefits | Assets measured at NAV | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 326.9 | 282.6 | |
Evergy Kansas Central | Pension Benefits | Domestic equities | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 233.8 | 215 | |
Evergy Kansas Central | Pension Benefits | Domestic equities | Level 1 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 150.6 | 144.7 | |
Evergy Kansas Central | Pension Benefits | Domestic equities | Level 2 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Kansas Central | Pension Benefits | Domestic equities | Level 3 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Kansas Central | Pension Benefits | Domestic equities | Assets measured at NAV | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 83.2 | 70.3 | |
Evergy Kansas Central | Pension Benefits | International equities | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 162.4 | 138.7 | |
Evergy Kansas Central | Pension Benefits | International equities | Level 1 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 101.5 | 91.8 | |
Evergy Kansas Central | Pension Benefits | International equities | Level 2 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Kansas Central | Pension Benefits | International equities | Level 3 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Kansas Central | Pension Benefits | International equities | Assets measured at NAV | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 60.9 | 46.9 | |
Evergy Kansas Central | Pension Benefits | Bond funds | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 281.7 | 296.4 | |
Evergy Kansas Central | Pension Benefits | Bond funds | Level 1 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 233 | 255.4 | |
Evergy Kansas Central | Pension Benefits | Bond funds | Level 2 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Kansas Central | Pension Benefits | Bond funds | Level 3 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Kansas Central | Pension Benefits | Bond funds | Assets measured at NAV | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 48.7 | 41 | |
Evergy Kansas Central | Pension Benefits | Real estate investments | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 46.5 | 44.8 | |
Evergy Kansas Central | Pension Benefits | Real estate investments | Level 1 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Kansas Central | Pension Benefits | Real estate investments | Level 2 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Kansas Central | Pension Benefits | Real estate investments | Level 3 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Kansas Central | Pension Benefits | Real estate investments | Assets measured at NAV | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 46.5 | 44.8 | |
Evergy Kansas Central | Pension Benefits | Combination debt/equity/other fund | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 30.1 | 30.1 | |
Evergy Kansas Central | Pension Benefits | Combination debt/equity/other fund | Level 1 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 30.1 | 30.1 | |
Evergy Kansas Central | Pension Benefits | Combination debt/equity/other fund | Level 2 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Kansas Central | Pension Benefits | Combination debt/equity/other fund | Level 3 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Kansas Central | Pension Benefits | Combination debt/equity/other fund | Assets measured at NAV | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Kansas Central | Pension Benefits | Alternative investment funds | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 78.5 | 73.6 | |
Evergy Kansas Central | Pension Benefits | Alternative investment funds | Level 1 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Kansas Central | Pension Benefits | Alternative investment funds | Level 2 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Kansas Central | Pension Benefits | Alternative investment funds | Level 3 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Kansas Central | Pension Benefits | Alternative investment funds | Assets measured at NAV | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 78.5 | 73.6 | |
Evergy Kansas Central | Pension Benefits | Short-term investments | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 9.1 | 6 | |
Evergy Kansas Central | Pension Benefits | Short-term investments | Level 1 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Kansas Central | Pension Benefits | Short-term investments | Level 2 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Kansas Central | Pension Benefits | Short-term investments | Level 3 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Kansas Central | Pension Benefits | Short-term investments | Assets measured at NAV | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 9.1 | 6 | |
Evergy Kansas Central | Post-Retirement Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 120.5 | 109.7 | 124.1 |
Evergy Kansas Central | Post-Retirement Benefits | Level 1 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 1.1 | 0.2 | |
Evergy Kansas Central | Post-Retirement Benefits | Level 2 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Kansas Central | Post-Retirement Benefits | Level 3 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Kansas Central | Post-Retirement Benefits | Assets measured at NAV | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 119.4 | 109.5 | |
Evergy Kansas Central | Post-Retirement Benefits | Domestic equities | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 40.5 | 56.4 | |
Evergy Kansas Central | Post-Retirement Benefits | Domestic equities | Level 1 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Kansas Central | Post-Retirement Benefits | Domestic equities | Level 2 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Kansas Central | Post-Retirement Benefits | Domestic equities | Level 3 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Kansas Central | Post-Retirement Benefits | Domestic equities | Assets measured at NAV | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 40.5 | 56.4 | |
Evergy Kansas Central | Post-Retirement Benefits | International equities | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 26 | 14 | |
Evergy Kansas Central | Post-Retirement Benefits | International equities | Level 1 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Kansas Central | Post-Retirement Benefits | International equities | Level 2 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Kansas Central | Post-Retirement Benefits | International equities | Level 3 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Kansas Central | Post-Retirement Benefits | International equities | Assets measured at NAV | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 26 | 14 | |
Evergy Kansas Central | Post-Retirement Benefits | Bond funds | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 52.9 | 38.4 | |
Evergy Kansas Central | Post-Retirement Benefits | Bond funds | Level 1 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Kansas Central | Post-Retirement Benefits | Bond funds | Level 2 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Kansas Central | Post-Retirement Benefits | Bond funds | Level 3 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Kansas Central | Post-Retirement Benefits | Bond funds | Assets measured at NAV | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 52.9 | 38.4 | |
Evergy Kansas Central | Post-Retirement Benefits | Short-term investments | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | | 0.7 | |
Evergy Kansas Central | Post-Retirement Benefits | Short-term investments | Level 1 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | | 0 | |
Evergy Kansas Central | Post-Retirement Benefits | Short-term investments | Level 2 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | | 0 | |
Evergy Kansas Central | Post-Retirement Benefits | Short-term investments | Level 3 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | | 0 | |
Evergy Kansas Central | Post-Retirement Benefits | Short-term investments | Assets measured at NAV | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | | 0.7 | |
Evergy Kansas Central | Post-Retirement Benefits | Cash and cash equivalents | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 1.1 | 0.2 | |
Evergy Kansas Central | Post-Retirement Benefits | Cash and cash equivalents | Level 1 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 1.1 | 0.2 | |
Evergy Kansas Central | Post-Retirement Benefits | Cash and cash equivalents | Level 2 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Kansas Central | Post-Retirement Benefits | Cash and cash equivalents | Level 3 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Kansas Central | Post-Retirement Benefits | Cash and cash equivalents | Assets measured at NAV | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 890.7 | 798.8 | 848.4 |
Evergy Metro Inc | Pension Benefits | Level 1 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 499.7 | 450.2 | |
Evergy Metro Inc | Pension Benefits | Level 2 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 149.5 | 146.9 | |
Evergy Metro Inc | Pension Benefits | Level 3 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Pension Benefits | Assets measured at NAV | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 241.5 | 201.7 | |
Evergy Metro Inc | Pension Benefits | Domestic equities | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 244.8 | 238.1 | |
Evergy Metro Inc | Pension Benefits | Domestic equities | Level 1 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 195.3 | 198.6 | |
Evergy Metro Inc | Pension Benefits | Domestic equities | Level 2 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Pension Benefits | Domestic equities | Level 3 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Pension Benefits | Domestic equities | Assets measured at NAV | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 49.5 | 39.5 | |
Evergy Metro Inc | Pension Benefits | International equities | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 178.7 | 150.9 | |
Evergy Metro Inc | Pension Benefits | International equities | Level 1 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 117.7 | 104 | |
Evergy Metro Inc | Pension Benefits | International equities | Level 2 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Pension Benefits | International equities | Level 3 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Pension Benefits | International equities | Assets measured at NAV | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 61 | 46.9 | |
Evergy Metro Inc | Pension Benefits | Bond funds | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 71 | 67.4 | |
Evergy Metro Inc | Pension Benefits | Bond funds | Level 1 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 15.6 | 19.3 | |
Evergy Metro Inc | Pension Benefits | Bond funds | Level 2 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Pension Benefits | Bond funds | Level 3 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Pension Benefits | Bond funds | Assets measured at NAV | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 55.4 | 48.1 | |
Evergy Metro Inc | Pension Benefits | Real estate investments | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 50.8 | 48.2 | |
Evergy Metro Inc | Pension Benefits | Real estate investments | Level 1 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 12.8 | 12.6 | |
Evergy Metro Inc | Pension Benefits | Real estate investments | Level 2 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Pension Benefits | Real estate investments | Level 3 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Pension Benefits | Real estate investments | Assets measured at NAV | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 38 | 35.6 | |
Evergy Metro Inc | Pension Benefits | Combination debt/equity/other fund | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 11.9 | 13.5 | |
Evergy Metro Inc | Pension Benefits | Combination debt/equity/other fund | Level 1 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 11.9 | 13.5 | |
Evergy Metro Inc | Pension Benefits | Combination debt/equity/other fund | Level 2 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Pension Benefits | Combination debt/equity/other fund | Level 3 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Pension Benefits | Combination debt/equity/other fund | Assets measured at NAV | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Pension Benefits | Alternative investment funds | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 36.6 | 31.6 | |
Evergy Metro Inc | Pension Benefits | Alternative investment funds | Level 1 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Pension Benefits | Alternative investment funds | Level 2 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Pension Benefits | Alternative investment funds | Level 3 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Pension Benefits | Alternative investment funds | Assets measured at NAV | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 36.6 | 31.6 | |
Evergy Metro Inc | Pension Benefits | Short-term investments | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 1 | | |
Evergy Metro Inc | Pension Benefits | Short-term investments | Level 1 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | | |
Evergy Metro Inc | Pension Benefits | Short-term investments | Level 2 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | | |
Evergy Metro Inc | Pension Benefits | Short-term investments | Level 3 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | | |
Evergy Metro Inc | Pension Benefits | Short-term investments | Assets measured at NAV | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 1 | | |
Evergy Metro Inc | Pension Benefits | Corporate bonds | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 123.9 | 123.6 | |
Evergy Metro Inc | Pension Benefits | Corporate bonds | Level 1 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Pension Benefits | Corporate bonds | Level 2 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 123.9 | 123.6 | |
Evergy Metro Inc | Pension Benefits | Corporate bonds | Level 3 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Pension Benefits | Corporate bonds | Assets measured at NAV | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Pension Benefits | U.S. Treasury and agency bonds | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 70.9 | 69.9 | |
Evergy Metro Inc | Pension Benefits | U.S. Treasury and agency bonds | Level 1 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 53.5 | 52.4 | |
Evergy Metro Inc | Pension Benefits | U.S. Treasury and agency bonds | Level 2 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 17.4 | 17.5 | |
Evergy Metro Inc | Pension Benefits | U.S. Treasury and agency bonds | Level 3 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Pension Benefits | U.S. Treasury and agency bonds | Assets measured at NAV | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Pension Benefits | Mortgage and asset backed securities | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 5.7 | 5.5 | |
Evergy Metro Inc | Pension Benefits | Mortgage and asset backed securities | Level 1 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Pension Benefits | Mortgage and asset backed securities | Level 2 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 5.7 | 5.5 | |
Evergy Metro Inc | Pension Benefits | Mortgage and asset backed securities | Level 3 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Pension Benefits | Mortgage and asset backed securities | Assets measured at NAV | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Pension Benefits | Cash and cash equivalents | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 92.9 | 49.8 | |
Evergy Metro Inc | Pension Benefits | Cash and cash equivalents | Level 1 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 92.9 | 49.8 | |
Evergy Metro Inc | Pension Benefits | Cash and cash equivalents | Level 2 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Pension Benefits | Cash and cash equivalents | Level 3 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Pension Benefits | Cash and cash equivalents | Assets measured at NAV | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Pension Benefits | Other | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 2.5 | 0.3 | |
Evergy Metro Inc | Pension Benefits | Other | Level 1 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Pension Benefits | Other | Level 2 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 2.5 | 0.3 | |
Evergy Metro Inc | Pension Benefits | Other | Level 3 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Pension Benefits | Other | Assets measured at NAV | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Post-Retirement Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 119.4 | 113.6 | $ 115.8 |
Evergy Metro Inc | Post-Retirement Benefits | Level 1 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 15.2 | 10.9 | |
Evergy Metro Inc | Post-Retirement Benefits | Level 2 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 26.8 | 27.9 | |
Evergy Metro Inc | Post-Retirement Benefits | Level 3 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Post-Retirement Benefits | Assets measured at NAV | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 77.4 | 74.8 | |
Evergy Metro Inc | Post-Retirement Benefits | Domestic equities | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 3.2 | 2.5 | |
Evergy Metro Inc | Post-Retirement Benefits | Domestic equities | Level 1 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 3.2 | 2.5 | |
Evergy Metro Inc | Post-Retirement Benefits | Domestic equities | Level 2 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Post-Retirement Benefits | Domestic equities | Level 3 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Post-Retirement Benefits | Domestic equities | Assets measured at NAV | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Post-Retirement Benefits | International equities | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 1.1 | 0.9 | |
Evergy Metro Inc | Post-Retirement Benefits | International equities | Level 1 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 1.1 | 0.9 | |
Evergy Metro Inc | Post-Retirement Benefits | International equities | Level 2 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Post-Retirement Benefits | International equities | Level 3 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Post-Retirement Benefits | International equities | Assets measured at NAV | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Post-Retirement Benefits | Bond funds | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 77.5 | 75 | |
Evergy Metro Inc | Post-Retirement Benefits | Bond funds | Level 1 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0.1 | 0.2 | |
Evergy Metro Inc | Post-Retirement Benefits | Bond funds | Level 2 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Post-Retirement Benefits | Bond funds | Level 3 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Post-Retirement Benefits | Bond funds | Assets measured at NAV | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 77.4 | 74.8 | |
Evergy Metro Inc | Post-Retirement Benefits | Corporate bonds | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 17.8 | 17.4 | |
Evergy Metro Inc | Post-Retirement Benefits | Corporate bonds | Level 1 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Post-Retirement Benefits | Corporate bonds | Level 2 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 17.8 | 17.4 | |
Evergy Metro Inc | Post-Retirement Benefits | Corporate bonds | Level 3 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Post-Retirement Benefits | Corporate bonds | Assets measured at NAV | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Post-Retirement Benefits | U.S. Treasury and agency bonds | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 11.5 | 10.3 | |
Evergy Metro Inc | Post-Retirement Benefits | U.S. Treasury and agency bonds | Level 1 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 4.1 | 2.6 | |
Evergy Metro Inc | Post-Retirement Benefits | U.S. Treasury and agency bonds | Level 2 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 7.4 | 7.7 | |
Evergy Metro Inc | Post-Retirement Benefits | U.S. Treasury and agency bonds | Level 3 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Post-Retirement Benefits | U.S. Treasury and agency bonds | Assets measured at NAV | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Post-Retirement Benefits | Mortgage and asset backed securities | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 1.3 | 2.5 | |
Evergy Metro Inc | Post-Retirement Benefits | Mortgage and asset backed securities | Level 1 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Post-Retirement Benefits | Mortgage and asset backed securities | Level 2 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 1.3 | 2.5 | |
Evergy Metro Inc | Post-Retirement Benefits | Mortgage and asset backed securities | Level 3 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Post-Retirement Benefits | Mortgage and asset backed securities | Assets measured at NAV | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Post-Retirement Benefits | Cash and cash equivalents | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 6.7 | 4.7 | |
Evergy Metro Inc | Post-Retirement Benefits | Cash and cash equivalents | Level 1 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 6.7 | 4.7 | |
Evergy Metro Inc | Post-Retirement Benefits | Cash and cash equivalents | Level 2 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Post-Retirement Benefits | Cash and cash equivalents | Level 3 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Post-Retirement Benefits | Cash and cash equivalents | Assets measured at NAV | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Post-Retirement Benefits | Other | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0.3 | 0.3 | |
Evergy Metro Inc | Post-Retirement Benefits | Other | Level 1 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Post-Retirement Benefits | Other | Level 2 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0.3 | 0.3 | |
Evergy Metro Inc | Post-Retirement Benefits | Other | Level 3 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | 0 | 0 | |
Evergy Metro Inc | Post-Retirement Benefits | Other | Assets measured at NAV | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Fair value of plan assets | $ 0 | $ 0 | |