XML 133 R101.htm IDEA: XBRL DOCUMENT
v3.20.4

PENSION PLANS AND POST-RETIREMENT BENEFITS - Fair Values of Assets (Details) - USD ($) $ in Millions | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | --- | ---
Pension Benefits |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | $ 1,799.1 | $ 1,732.8 | $ 1,603.4
Post-Retirement Benefits |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 248.3 | 239.9 | 223.3
Evergy Kansas Central | Pension Benefits |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 887.0 | 842.1 | 804.6
Evergy Kansas Central | Pension Benefits | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 516.2 | 515.2 |
Evergy Kansas Central | Pension Benefits | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Kansas Central | Pension Benefits | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Kansas Central | Pension Benefits | Assets measured at NAV |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 370.8 | 326.9 |
Evergy Kansas Central | Pension Benefits | Domestic equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 248.5 | 233.8 |
Evergy Kansas Central | Pension Benefits | Domestic equities | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 151.3 | 150.6 |
Evergy Kansas Central | Pension Benefits | Domestic equities | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Kansas Central | Pension Benefits | Domestic equities | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Kansas Central | Pension Benefits | Domestic equities | Assets measured at NAV |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 97.2 | 83.2 |
Evergy Kansas Central | Pension Benefits | International equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 171.2 | 162.4 |
Evergy Kansas Central | Pension Benefits | International equities | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 103.8 | 101.5 |
Evergy Kansas Central | Pension Benefits | International equities | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Kansas Central | Pension Benefits | International equities | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Kansas Central | Pension Benefits | International equities | Assets measured at NAV |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 67.4 | 60.9 |
Evergy Kansas Central | Pension Benefits | Bond funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 281.2 | 281.7 |
Evergy Kansas Central | Pension Benefits | Bond funds | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 230.7 | 233.0 |
Evergy Kansas Central | Pension Benefits | Bond funds | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Kansas Central | Pension Benefits | Bond funds | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Kansas Central | Pension Benefits | Bond funds | Assets measured at NAV |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 50.5 | 48.7 |
Evergy Kansas Central | Pension Benefits | Real estate investments |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 46.7 | 46.5 |
Evergy Kansas Central | Pension Benefits | Real estate investments | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 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 | 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 | 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 | 46.7 | 46.5 |
Evergy Kansas Central | Pension Benefits | Combination debt/equity/other fund |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 30.4 | 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 | 30.4 | 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 | 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 | 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 | 0.0 |
Evergy Kansas Central | Pension Benefits | Alternative investment funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 83.6 | 78.5 |
Evergy Kansas Central | Pension Benefits | Alternative investment funds | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 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 | 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 | 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 | 83.6 | 78.5 |
Evergy Kansas Central | Pension Benefits | Short-term investments |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 25.4 | 9.1 |
Evergy Kansas Central | Pension Benefits | Short-term investments | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 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 | 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 | 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 | 25.4 | 9.1 |
Evergy Kansas Central | Post-Retirement Benefits |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 125.8 | 120.5 | 109.7
Evergy Kansas Central | Post-Retirement Benefits | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.7 | 1.1 |
Evergy Kansas Central | Post-Retirement Benefits | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Kansas Central | Post-Retirement Benefits | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Kansas Central | Post-Retirement Benefits | Assets measured at NAV |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 125.1 | 119.4 |
Evergy Kansas Central | Post-Retirement Benefits | Domestic equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 41.9 | 40.5 |
Evergy Kansas Central | Post-Retirement Benefits | Domestic equities | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 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 | 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 | 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 | 41.9 | 40.5 |
Evergy Kansas Central | Post-Retirement Benefits | International equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 27.7 | 26.0 |
Evergy Kansas Central | Post-Retirement Benefits | International equities | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 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 | 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 | 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 | 27.7 | 26.0 |
Evergy Kansas Central | Post-Retirement Benefits | Bond funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 55.5 | 52.9 |
Evergy Kansas Central | Post-Retirement Benefits | Bond funds | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 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 | 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 | 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 | 55.5 | 52.9 |
Evergy Kansas Central | Post-Retirement Benefits | Cash and cash equivalents |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.7 | 1.1 |
Evergy Kansas Central | Post-Retirement Benefits | Cash and cash equivalents | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.7 | 1.1 |
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 | 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 | 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 | 0.0 |
Evergy Metro | Pension Benefits |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 912.1 | 890.7 | 798.8
Evergy Metro | Pension Benefits | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 502.4 | 499.7 |
Evergy Metro | Pension Benefits | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 150.1 | 149.5 |
Evergy Metro | Pension Benefits | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | Pension Benefits | Assets measured at NAV |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 259.6 | 241.5 |
Evergy Metro | Pension Benefits | Domestic equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 247.4 | 244.8 |
Evergy Metro | Pension Benefits | Domestic equities | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 191.9 | 195.3 |
Evergy Metro | Pension Benefits | Domestic equities | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | Pension Benefits | Domestic equities | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | Pension Benefits | Domestic equities | Assets measured at NAV |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 55.5 | 49.5 |
Evergy Metro | Pension Benefits | International equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 220.8 | 178.7 |
Evergy Metro | Pension Benefits | International equities | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 153.4 | 117.7 |
Evergy Metro | Pension Benefits | International equities | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | Pension Benefits | International equities | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | Pension Benefits | International equities | Assets measured at NAV |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 67.4 | 61.0 |
Evergy Metro | Pension Benefits | Bond funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 78.1 | 71.0 |
Evergy Metro | Pension Benefits | Bond funds | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 21.1 | 15.6 |
Evergy Metro | Pension Benefits | Bond funds | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | Pension Benefits | Bond funds | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | Pension Benefits | Bond funds | Assets measured at NAV |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 57.0 | 55.4 |
Evergy Metro | Pension Benefits | Corporate bonds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 133.6 | 123.9 |
Evergy Metro | Pension Benefits | Corporate bonds | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | Pension Benefits | Corporate bonds | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 133.6 | 123.9 |
Evergy Metro | Pension Benefits | Corporate bonds | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | Pension Benefits | Corporate bonds | Assets measured at NAV |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | Pension Benefits | U.S. Treasury and agency bonds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 73.8 | 70.9 |
Evergy Metro | Pension Benefits | U.S. Treasury and agency bonds | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 61.5 | 53.5 |
Evergy Metro | Pension Benefits | U.S. Treasury and agency bonds | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 12.3 | 17.4 |
Evergy Metro | Pension Benefits | U.S. Treasury and agency bonds | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | 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 | 0.0 |
Evergy Metro | Pension Benefits | Mortgage and asset backed securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 5.0 | 5.7 |
Evergy Metro | Pension Benefits | Mortgage and asset backed securities | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | Pension Benefits | Mortgage and asset backed securities | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 5.0 | 5.7 |
Evergy Metro | Pension Benefits | Mortgage and asset backed securities | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | Pension Benefits | Mortgage and asset backed securities | Assets measured at NAV |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | Pension Benefits | Real estate investments |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 40.2 | 50.8 |
Evergy Metro | Pension Benefits | Real estate investments | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 1.6 | 12.8 |
Evergy Metro | Pension Benefits | Real estate investments | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | Pension Benefits | Real estate investments | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | Pension Benefits | Real estate investments | Assets measured at NAV |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 38.6 | 38.0 |
Evergy Metro | Pension Benefits | Combination debt/equity/other fund |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 15.6 | 11.9 |
Evergy Metro | Pension Benefits | Combination debt/equity/other fund | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 15.6 | 11.9 |
Evergy Metro | Pension Benefits | Combination debt/equity/other fund | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | Pension Benefits | Combination debt/equity/other fund | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | Pension Benefits | Combination debt/equity/other fund | Assets measured at NAV |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | Pension Benefits | Alternative investment funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 39.7 | 36.6 |
Evergy Metro | Pension Benefits | Alternative investment funds | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | Pension Benefits | Alternative investment funds | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | Pension Benefits | Alternative investment funds | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | Pension Benefits | Alternative investment funds | Assets measured at NAV |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 39.7 | 36.6 |
Evergy Metro | Pension Benefits | Cash and cash equivalents |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 57.3 | 92.9 |
Evergy Metro | Pension Benefits | Cash and cash equivalents | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 57.3 | 92.9 |
Evergy Metro | Pension Benefits | Cash and cash equivalents | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | Pension Benefits | Cash and cash equivalents | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | Pension Benefits | Cash and cash equivalents | Assets measured at NAV |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | Pension Benefits | Short-term investments |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 1.4 | 1.0 |
Evergy Metro | Pension Benefits | Short-term investments | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | Pension Benefits | Short-term investments | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | Pension Benefits | Short-term investments | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | Pension Benefits | Short-term investments | Assets measured at NAV |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 1.4 | 1.0 |
Evergy Metro | Pension Benefits | Other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | (0.8) | 2.5 |
Evergy Metro | Pension Benefits | Other | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | Pension Benefits | Other | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | (0.8) | 2.5 |
Evergy Metro | Pension Benefits | Other | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | Pension Benefits | Other | Assets measured at NAV |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | Post-Retirement Benefits |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 122.5 | 119.4 | $ 113.6
Evergy Metro | Post-Retirement Benefits | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 17.1 | 15.2 |
Evergy Metro | Post-Retirement Benefits | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 26.6 | 26.8 |
Evergy Metro | Post-Retirement Benefits | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | Post-Retirement Benefits | Assets measured at NAV |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 78.8 | 77.4 |
Evergy Metro | Post-Retirement Benefits | Domestic equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 4.6 | 3.2 |
Evergy Metro | Post-Retirement Benefits | Domestic equities | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 4.6 | 3.2 |
Evergy Metro | Post-Retirement Benefits | Domestic equities | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | Post-Retirement Benefits | Domestic equities | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | Post-Retirement Benefits | Domestic equities | Assets measured at NAV |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | Post-Retirement Benefits | International equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 1.2 | 1.1 |
Evergy Metro | Post-Retirement Benefits | International equities | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 1.2 | 1.1 |
Evergy Metro | Post-Retirement Benefits | International equities | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | Post-Retirement Benefits | International equities | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | Post-Retirement Benefits | International equities | Assets measured at NAV |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | Post-Retirement Benefits | Bond funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 79.0 | 77.5 |
Evergy Metro | Post-Retirement Benefits | Bond funds | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.2 | 0.1 |
Evergy Metro | Post-Retirement Benefits | Bond funds | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | Post-Retirement Benefits | Bond funds | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | Post-Retirement Benefits | Bond funds | Assets measured at NAV |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 78.8 | 77.4 |
Evergy Metro | Post-Retirement Benefits | Corporate bonds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 17.9 | 17.8 |
Evergy Metro | Post-Retirement Benefits | Corporate bonds | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | Post-Retirement Benefits | Corporate bonds | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 17.9 | 17.8 |
Evergy Metro | Post-Retirement Benefits | Corporate bonds | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | Post-Retirement Benefits | Corporate bonds | Assets measured at NAV |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | Post-Retirement Benefits | U.S. Treasury and agency bonds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 13.6 | 11.5 |
Evergy Metro | Post-Retirement Benefits | U.S. Treasury and agency bonds | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 5.7 | 4.1 |
Evergy Metro | Post-Retirement Benefits | U.S. Treasury and agency bonds | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 7.9 | 7.4 |
Evergy Metro | Post-Retirement Benefits | U.S. Treasury and agency bonds | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | 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 | 0.0 |
Evergy Metro | Post-Retirement Benefits | Mortgage and asset backed securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.5 | 1.3 |
Evergy Metro | Post-Retirement Benefits | Mortgage and asset backed securities | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | Post-Retirement Benefits | Mortgage and asset backed securities | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.5 | 1.3 |
Evergy Metro | Post-Retirement Benefits | Mortgage and asset backed securities | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | 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 | 0.0 |
Evergy Metro | Post-Retirement Benefits | Cash and cash equivalents |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 5.4 | 6.7 |
Evergy Metro | Post-Retirement Benefits | Cash and cash equivalents | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 5.4 | 6.7 |
Evergy Metro | Post-Retirement Benefits | Cash and cash equivalents | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | Post-Retirement Benefits | Cash and cash equivalents | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | Post-Retirement Benefits | Cash and cash equivalents | Assets measured at NAV |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | Post-Retirement Benefits | Other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.3 | 0.3 |
Evergy Metro | Post-Retirement Benefits | Other | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | Post-Retirement Benefits | Other | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.3 | 0.3 |
Evergy Metro | Post-Retirement Benefits | Other | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Evergy Metro | Post-Retirement Benefits | Other | Assets measured at NAV |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | $ 0.0 | $ 0.0 |

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_DefinedBenefitPlanDisclosureLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(iv)(01) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(iv)(01) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(ii) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 Reference 4: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=118257860&loc=d3e4179-114921 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(iv)(02) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 Reference 7: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(ii) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
Name: | us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_RetirementPlanTypeAxis=us-gaap_PensionPlansDefinedBenefitMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RetirementPlanTypeAxis=us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=evrg_EvergyKansasCentralIncMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel1Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel2Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel3Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueMeasuredAtNetAssetValuePerShareMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=us-gaap_DefinedBenefitPlanEquitySecuritiesUsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=us-gaap_DefinedBenefitPlanEquitySecuritiesNonUsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=us-gaap_FixedIncomeFundsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=us-gaap_DefinedBenefitPlanRealEstateMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=us-gaap_BalancedFundsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=evrg_AlternativeInvestmentFundsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=us-gaap_ShortTermInvestmentsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=us-gaap_DefinedBenefitPlanCashAndCashEquivalentsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=evrg_EvergyMetroIncMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=us-gaap_CorporateDebtSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=us-gaap_USTreasuryAndGovernmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=us-gaap_AssetBackedSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=evrg_DefinedBenefitPlanOtherMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |