CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY (Unaudited) - USD ($) shares in Millions, $ in Millions	Total	OG&E [Member]	Common Stock	Common Stock OG&E [Member]	Treasury Stock	Premium on Common Stock	Premium on Common Stock OG&E [Member]	Retained Earnings	Retained Earnings OG&E [Member]	Accumulated Other Comprehensive Income (Loss)
Balance at Dec. 31, 2021	$ 4,056.3	$ 4,602.8	$ 2.0	$ 100.9	$ (0.1)	$ 1,123.8	$ 1,470.8	$ 2,955.4	$ 3,031.1	$ (24.8)
Common Stock, Shares, Outstanding at Dec. 31, 2021			200.1	40.4
Treasury Stock, Common, Shares at Dec. 31, 2021					0.0
Changes in Stockholders' Equity
Net income	279.5	39.0	$ 0.0	$ 0.0	$ 0.0	0.0	0.0	279.5	39.0	0.0
Net income, Number of Shares			0.0	0.0	0.0
Other comprehensive income, net of tax	7.8	0.0	$ 0.0		$ 0.0	0.0		0.0		7.8
Other comprehensive income, net of tax, Number of Shares			0.0		0.0
Dividends declared on common stock	(82.3)		$ 0.0		$ 0.0	0.0		(82.3)		0.0
Dividends declared on common stock, Number of Shares			0.0		0.0
Stock-based compensation	1.4	0.8	$ 0.0	$ 0.0	$ 0.0	1.4	0.8	0.0	0.0	0.0
Stock-based compensation, Number of Shares			0.0	0.0	0.0
Balance at Mar. 31, 2022	4,262.7	4,642.6	$ 2.0	$ 100.9	$ (0.1)	1,125.2	1,471.6	3,152.6	3,070.1	(17.0)
Common Stock, Shares, Outstanding at Mar. 31, 2022			200.1	40.4
Treasury Stock, Common, Shares at Mar. 31, 2022					0.0
Balance at Dec. 31, 2022	4,413.4	5,045.2	$ 2.0	$ 100.9	$ (0.1)	1,132.5	1,473.7	3,290.9	3,470.6	(11.9)
Common Stock, Shares, Outstanding at Dec. 31, 2022			200.2	40.4
Treasury Stock, Common, Shares at Dec. 31, 2022					0.0
Changes in Stockholders' Equity
Net income	38.3	39.8	$ 0.0	$ 0.0	$ 0.0	0.0	0.0	38.3	39.8	0.0
Net income, Number of Shares			0.0	0.0	0.0
Other comprehensive income, net of tax	1.1	0.0	$ 0.0		$ 0.0	0.0		0.0		1.1
Other comprehensive income, net of tax, Number of Shares			0.0		0.0
Dividends declared on common stock	(83.6)		$ 0.0		$ 0.0	0.0		(83.6)		0.0
Dividends declared on common stock, Number of Shares			0.0		0.0
Stock-based compensation	0.8	0.6	$ 0.0	$ 0.0	$ 0.1	0.7	0.6	0.0	0.0	0.0
Stock-based compensation, Number of Shares			0.1	0.0	0.0
Balance at Mar. 31, 2023	$ 4,370.0	$ 5,085.6	$ 2.0	$ 100.9	$ 0.0	$ 1,133.2	$ 1,474.3	$ 3,245.6	$ 3,510.4	$ (10.8)
Common Stock, Shares, Outstanding at Mar. 31, 2023			200.3	40.4
Treasury Stock, Common, Shares at Mar. 31, 2023					0.0