SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Property, Plant and Equipment (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Property, Plant and Equipment [Line Items]
Depreciation rates average	3.00%
Regulatory assets	$ 2,214.3	$ 2,415.2
Minimum
Property, Plant and Equipment [Line Items]
Generating facilities	8 years
Transmission facilities	15 years
Distribution facilities	8 years
Other	5 years
Maximum
Property, Plant and Equipment [Line Items]
Generating facilities	87 years
Transmission facilities	94 years
Distribution facilities	73 years
Other	84 years
Evergy Kansas Central
Property, Plant and Equipment [Line Items]
Regulatory assets	$ 711.9	1,010.9
Evergy Kansas Central | Minimum
Property, Plant and Equipment [Line Items]
Generating facilities	8 years
Transmission facilities	36 years
Distribution facilities	19 years
Other	7 years
Evergy Kansas Central | Maximum
Property, Plant and Equipment [Line Items]
Generating facilities	87 years
Transmission facilities	94 years
Distribution facilities	73 years
Other	84 years
Evergy Metro
Property, Plant and Equipment [Line Items]
Regulatory assets	$ 373.8	$ 497.0
Evergy Metro | Minimum
Property, Plant and Equipment [Line Items]
Generating facilities	20 years
Transmission facilities	15 years
Distribution facilities	8 years
Other	5 years
Evergy Metro | Maximum
Property, Plant and Equipment [Line Items]
Generating facilities	60 years
Transmission facilities	70 years
Distribution facilities	55 years
Other	50 years