CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY - USD ($) $ in Millions	Total	OG&E [Member]	Common Stock	Common Stock OG&E [Member]	Premium on Common Stock	Premium on Common Stock OG&E [Member]	Retained Earnings	Retained Earnings OG&E [Member]	Accumulated Other Comprehensive Income (Loss)	Treasury Stock [Member]
Balance at Dec. 31, 2019	$ 4,139.5	$ 3,958.3	$ 2.0	$ 100.9	$ 1,129.3	$ 935.7	$ 3,036.1	$ 2,921.7	$ (27.9)	$ 0.0
Common Stock, Shares, Outstanding at Dec. 31, 2019			200,100,000	40,400,000
Treasury Stock, Common, Shares at Dec. 31, 2019										0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(173.7)	339.4	$ 0.0	$ 0.0	0.0	0.0	(173.7)	339.4	0.0	$ 0.0
Net income (loss), Number of Shares			0	0						0
Other comprehensive income (loss), net of tax, Number of Shares			0							0
Other comprehensive income (loss), net of tax	(4.2)	0.0	$ 0.0		0.0		0.0		(4.2)	$ 0.0
Dividends declared on common stock, Number of Shares			0	0						0
Dividends declared on common stock	(317.8)	(325.0)	$ 0.0	$ 0.0	0.0	0.0	(317.8)	(325.0)	0.0	$ 0.0
Purchase of treasury stock, Value	$ (14.7)		$ 0.0		0.0		0.0		0.0	$ (14.7)
Purchase of treasury stock, Number of Shares	405,000		0							400,000
Stock-based compensation, Number of Shares			0							(300,000)
Stock-based compensation	$ 2.7	2.9	$ 0.0	0.0	(6.7)	2.9	0.0	0.0	0.0	$ 9.4
Balance at Dec. 31, 2020	3,631.8	3,975.6	$ 2.0	$ 100.9	1,122.6	938.6	2,544.6	2,936.1	(32.1)	$ (5.3)
Common Stock, Shares, Outstanding at Dec. 31, 2020			200,100,000	40,400,000
Treasury Stock, Common, Shares at Dec. 31, 2020										100,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	737.3	360.0	$ 0.0	$ 0.0	0.0	0.0	737.3	360.0	0.0	$ 0.0
Net income (loss), Number of Shares			0	0						0
Other comprehensive income (loss), net of tax, Number of Shares			0							0
Other comprehensive income (loss), net of tax	7.3	0.0	$ 0.0		0.0		0.0		7.3	$ 0.0
Dividends declared on common stock, Number of Shares			0	0						0
Dividends declared on common stock	(326.5)	(265.0)	$ 0.0	$ 0.0	0.0	0.0	(326.5)	(265.0)	0.0	$ 0.0
Capital contribution from OGE Energy		530.0		$ 0.0		530.0		0.0
Capital contribution from OGE Energy, Number of Shares				0
Stock-based compensation, Number of Shares			0	0						(100,000)
Stock-based compensation	6.4	2.2	$ 0.0	$ 0.0	1.2	2.2	0.0	0.0	0.0	$ 5.2
Balance at Dec. 31, 2021	$ 4,056.3	$ 4,602.8	$ 2.0	$ 100.9	1,123.8	1,470.8	2,955.4	3,031.1	(24.8)	$ (0.1)
Common Stock, Shares, Outstanding at Dec. 31, 2021	200,100,000	40,400,000	200,100,000	40,400,000
Treasury Stock, Common, Shares at Dec. 31, 2021	0.0									0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	$ 665.7	$ 439.5	$ 0.0	$ 0.0	0.0	0.0	665.7	439.5	0.0	$ 0.0
Net income (loss), Number of Shares			0	0						0
Other comprehensive income (loss), net of tax, Number of Shares			0							0
Other comprehensive income (loss), net of tax	12.9	0.0	$ 0.0		0.0		0.0		12.9	$ 0.0
Dividends declared on common stock, Number of Shares			0							0
Dividends declared on common stock	(330.2)		$ 0.0		0.0		(330.2)		0.0	$ 0.0
Stock-based compensation, Number of Shares			100,000	0						0
Stock-based compensation	8.7	2.9	$ 0.0	$ 0.0	8.7	2.9	0.0	0.0	0.0	$ 0.0
Balance at Dec. 31, 2022	$ 4,413.4	$ 5,045.2	$ 2.0	$ 100.9	$ 1,132.5	$ 1,473.7	$ 3,290.9	$ 3,470.6	$ (11.9)	$ (0.1)
Common Stock, Shares, Outstanding at Dec. 31, 2022	200,200,000	40,400,000	200,200,000	40,400,000
Treasury Stock, Common, Shares at Dec. 31, 2022	0.0									0