Derivative Instruments - Notional Amounts (Details) - Not Designated as Hedging Instrument [Member] MWh in Millions, MMBTU in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2023 MWh MMBTU	Dec. 31, 2022 MWh MMBTU
Natural gas commodity contract
Price Risk Derivatives [Abstract]
Derivative, Nonmonetary Notional Amount, Energy Measure | MMBTU	367.6	772.7
Power commodity contract
Price Risk Derivatives [Abstract]
Derivative, Nonmonetary Notional Amount, Energy Measure	26.0	67.2
Evergy Kansas Central | Natural gas commodity contract
Price Risk Derivatives [Abstract]
Derivative, Nonmonetary Notional Amount, Energy Measure | MMBTU	361.2	769.6
Evergy Kansas Central | Power commodity contract
Price Risk Derivatives [Abstract]
Derivative, Nonmonetary Notional Amount, Energy Measure	15.7	41.6
Evergy Metro | Power commodity contract
Price Risk Derivatives [Abstract]
Derivative, Nonmonetary Notional Amount, Energy Measure	7.3	18.2