ORGANIZATION AND BASIS OF PRESENTATION - Supplemental Cash Flow Information (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Cash paid for (received from):
Interest, net of amount capitalized	$ 105.3	$ 133.0
Income taxes, net of refunds	(0.2)	(0.5)
Right-of-use assets obtained in exchange for new operating lease liabilities	1.9	6.2
Right-of-use assets obtained in exchange for new finance lease liabilities	5.1	0.0
Non-cash investing transactions:
Property, plant and equipment additions	105.1	112.1
Evergy Kansas Central
Cash paid for (received from):
Interest, net of amount capitalized	48.8	56.3
Income taxes, net of refunds	(0.2)	(0.2)
Right-of-use assets obtained in exchange for new operating lease liabilities	0.7	2.7
Right-of-use assets obtained in exchange for new finance lease liabilities	1.3	0.0
Non-cash investing transactions:
Property, plant and equipment additions	47.6	54.8
Evergy Metro
Cash paid for (received from):
Interest, net of amount capitalized	21.3	31.1
Right-of-use assets obtained in exchange for new operating lease liabilities	1.0	3.5
Right-of-use assets obtained in exchange for new finance lease liabilities	3.5	0.0
Non-cash investing transactions:
Property, plant and equipment additions	$ 39.9	$ 41.0