RECEIVABLES - Allowance for Credit Loses (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning balance January 1	$ 32.9	$ 19.3
Credit loss expense	4.9	7.6
Write-offs	(21.6)	(17.1)
Recoveries of prior write-offs	8.5	9.2
Ending balance September 30	24.7	19.0
Evergy Kansas Central
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning balance January 1	13.0	7.5
Credit loss expense	5.4	3.2
Write-offs	(10.1)	(6.9)
Recoveries of prior write-offs	3.4	3.5
Ending balance September 30	11.7	7.3
Evergy Metro
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning balance January 1	13.3	8.1
Credit loss expense	(0.4)	2.8
Write-offs	(7.8)	(6.9)
Recoveries of prior write-offs	3.5	4.0
Ending balance September 30	$ 8.6	$ 8.0