RATE MATTERS AND REGULATION - Narrative (Details) $ in Millions		1 Months Ended				12 Months Ended
	Oct. 31, 2023 USD ($)	Feb. 28, 2024 USD ($)	Sep. 30, 2023 USD ($)	May 31, 2023 USD ($)	Apr. 30, 2023 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Regulatory Proceedings [Line Items]
Regulatory assets						$ 2,087.4	$ 2,214.3
Regulatory liabilities						$ 2,725.5	2,722.2
Interest rate						5.06%
TFR Refund
Regulatory Proceedings [Line Items]
Regulatory liabilities						$ 11.2	55.5
Fuel recovery mechanisms
Regulatory Proceedings [Line Items]
Regulatory liabilities						$ 34.7	4.7
Regulatory Liability, Amortization Period						1 year
February 2021 winter weather event
Regulatory Proceedings [Line Items]
Regulatory assets						$ 403.5	430.9
Evergy Kansas Central
Regulatory Proceedings [Line Items]
Regulatory assets						632.9	711.9
Regulatory liabilities						1,536.5	1,441.0
Evergy Kansas Central | TFR Refund
Regulatory Proceedings [Line Items]
Regulatory liabilities						11.2	55.5
Evergy Kansas Central | Fuel recovery mechanisms
Regulatory Proceedings [Line Items]
Regulatory liabilities						34.7	4.5
Evergy Kansas Central | February 2021 winter weather event
Regulatory Proceedings [Line Items]
Regulatory assets						79.7	121.9
Evergy Metro
Regulatory Proceedings [Line Items]
Regulatory assets						434.0	373.8
Regulatory liabilities						903.2	928.1
Evergy Metro | TFR Refund
Regulatory Proceedings [Line Items]
Regulatory liabilities						0.0	0.0
Evergy Metro | Fuel recovery mechanisms
Regulatory Proceedings [Line Items]
Regulatory liabilities						0.0	0.2
Evergy Metro | February 2021 winter weather event
Regulatory Proceedings [Line Items]
Regulatory assets						$ 0.0	0.0
Evergy Metro | Missouri Public Service Commission
Regulatory Proceedings [Line Items]
Public Utilities, Recovery Mechanism's Sharing Percentage for Fuel Cost						0.05
Evergy Missouri West | Missouri Public Service Commission
Regulatory Proceedings [Line Items]
Public Utilities, Recovery Mechanism Percent for Fuel Cost						0.95
La Cygne Station | Evergy Kansas South Inc
Regulatory Proceedings [Line Items]
VIE ownership percentage						50.00%
2023 Rate case proceedings | Evergy Kansas Central
Regulatory Proceedings [Line Items]
Annual revenue rate increase (decrease), requested					$ 204.0
Jointly owned utility plant, proportionate ownership share			8.00%		8.00%
Public Utilities, Approved Rate Increase (Decrease), Amount			$ 74.0
Public Utilities, Approved Rate Increase Decrease, Amount, Wind Farm	$ 18.6
Cost of investment in renewable generation, net of cash acquired					$ 220.9
Annual wind farm revenue rate increase (decrease), requested	$ 18.6				$ 21.5
Deferral of revenues to regulatory liability for refund to customers for COLI rate credits			96.5
Return on equity, requested					10.25%
Rate-making equity ratio, requested					52.00%
Persimmon Creek costs recovery period	20 years
2023 Rate case proceedings | Evergy Kansas Central | COLI Rate Credits for Refund
Regulatory Proceedings [Line Items]
Regulatory Liability, Amortization Period	3 years
2023 Rate case proceedings | Evergy Metro
Regulatory Proceedings [Line Items]
Annual revenue rate increase (decrease), requested					$ 14.0
Public Utilities, Approved Rate Increase (Decrease), Amount			$ (32.9)
Return on equity, requested					10.25%
Rate-making equity ratio, requested					52.00%
2018 Rate Case Proceedings | Evergy Kansas Central | Kansas Corporation Commission
Regulatory Proceedings [Line Items]
Refund percent on earnings over approved return on equity						0.50
Approved return on equity, percentage						9.30%
Estimated refund on earnings over approved return on equity						$ 0.0
2018 Rate Case Proceedings | Evergy Metro | Kansas Corporation Commission
Regulatory Proceedings [Line Items]
Refund percent on earnings over approved return on equity						0.50
Approved return on equity, percentage						9.30%
Estimated refund on earnings over approved return on equity						$ 16.7
Revised estimated refund on earnings over approved return on equity						6.0
Ordered refund on earnings over approved return on equity						6.0
Transmission delivery charge | Evergy Kansas Central | Kansas Corporation Commission
Regulatory Proceedings [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount				$ (22.3)
Transmission delivery charge | Evergy Metro | Kansas Corporation Commission
Regulatory Proceedings [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount				$ 4.0
2024 Rate case proceedings | Evergy Kansas Central | Federal Energy Regulatory Commission
Regulatory Proceedings [Line Items]
Annual transmissions revenue estimated amount of increase (decrease) over prior year						115.8
FERC 2024 TFR Proceeding | Evergy Metro | Federal Energy Regulatory Commission
Regulatory Proceedings [Line Items]
Annual transmissions revenue estimated amount of increase (decrease) over prior year						23.7
FERC 2023 TFR Proceeding | TFR Refund
Regulatory Proceedings [Line Items]
Regulatory liabilities							32.8
FERC 2023 TFR Proceeding | Evergy Kansas Central | Federal Energy Regulatory Commission
Regulatory Proceedings [Line Items]
Annual transmissions revenue estimated amount of increase (decrease) over prior year						(21.7)
FERC 2023 TFR Proceeding | Evergy Metro | Federal Energy Regulatory Commission
Regulatory Proceedings [Line Items]
Annual transmissions revenue estimated amount of increase (decrease) over prior year						8.6
FERC 2022 TFR Proceeding | Evergy Kansas Central | Federal Energy Regulatory Commission
Regulatory Proceedings [Line Items]
Annual transmissions revenue estimated amount of increase (decrease) over prior year						33.2
FERC 2022 TFR Proceeding | Evergy Metro | Federal Energy Regulatory Commission
Regulatory Proceedings [Line Items]
Annual transmissions revenue estimated amount of increase (decrease) over prior year						18.1
2021 MPSC Winter Weather Qualified Extraordinary Costs Securitization | Evergy Missouri West | 2021 Winter Weather Qualified Extraordinary Costs Securitization
Regulatory Proceedings [Line Items]
Regulatory assets						$ 323.8	$ 309.0
Subsequent Event | Evergy Missouri West
Regulatory Proceedings [Line Items]
Regulatory Asset, Amortization Period		15 years
Subsequent Event | 2024 Rate case proceedings | Evergy Missouri West
Regulatory Proceedings [Line Items]
Annual revenue rate increase (decrease), requested		$ 104.0
Return on equity, requested		10.50%
Rate-making equity ratio, requested		52.00%
Subsequent Event | 2021 MPSC Winter Weather Qualified Extraordinary Costs Securitization | Evergy Missouri West | Maximum
Regulatory Proceedings [Line Items]
Regulatory Asset, Amortization Period		17 years