CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	$ 416.8	$ 665.7	$ 737.3
Adjustments to reconcile net income to net cash provided from (used in) operating activities:
Depreciation and amortization	506.6	460.9	416.0
Deferred income taxes and other tax credits, net	11.6	(154.0)	125.9
(Gain) loss on investment in equity securities (Note 1)	0.0	(282.1)	8.6
Gain on Enable/Energy Transfer transaction (Note 1)	0.0	0.0	(353.0)
Equity in earnings of unconsolidated affiliates	0.0	0.0	(169.8)
Distributions from unconsolidated affiliates	0.0	0.0	73.4
Allowance for equity funds used during construction	(19.4)	(6.9)	(6.7)
Stock-based compensation expense	13.1	9.7	9.8
Regulatory assets	(92.1)	702.2	(874.9)
Regulatory liabilities	(12.2)	(9.1)	12.2
Other assets	0.0	18.9	(9.8)
Other liabilities	5.0	(6.6)	(8.1)
Change in certain current assets and liabilities:
Accounts receivable and accrued unbilled revenues, net	42.8	(97.0)	(1.9)
Income taxes receivable	2.5	(18.1)	5.5
Fuel, materials and supplies inventories	(122.8)	(130.1)	(3.4)
Fuel recoveries	535.4	(363.0)	(180.5)
Other current assets	44.6	(30.2)	(22.7)
Accounts payable	(136.3)	155.4	7.5
Other current liabilities	36.7	36.7	4.7
Net cash provided from (used in) operating activities	1,232.3	952.4	(229.9)
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures (less allowance for equity funds used during construction)	(1,178.2)	(1,050.9)	(778.5)
Proceeds from Sale of Equity Securities, FV-NI	0.0	1,067.2	0.0
Cash received in Enable/Energy Transfer transaction (Note 1)	0.0	0.0	35.0
Cost of removal and other	(93.9)	(112.7)	(89.0)
Net cash used in investing activities	(1,272.1)	(96.4)	(832.5)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from long-term debt	788.3	49.3	997.8
Payment of long-term debt	(1,000.1)	(0.1)	(0.1)
Increase (decrease) in short-term debt	499.2	(486.9)	391.9
Dividends paid on common stock	(333.2)	(329.3)	(324.9)
Cash paid for employee equity-based compensation and expense of common stock	(2.3)	(0.9)	(3.4)
Net cash (used in) provided from financing activities	(48.1)	(767.9)	1,061.3
NET CHANGE IN CASH AND CASH EQUIVALENTS	(87.9)	88.1	(1.1)
CASH AND CASH EQUIVALENTS AT BEGINNING OF YEAR	88.1	0.0	1.1
CASH AND CASH EQUIVALENTS AT END OF YEAR	0.2	88.1	0.0
SUPPLEMENTAL CASH FLOW INFORMATION
Interest (net of interest capitalized)	202.4	164.0	156.4
Income taxes (net of income tax refunds)	41.5	276.0	8.7
NON-CASH INVESTING AND FINANCING ACTIVITIES
Power plant long-term service agreement	0.7	0.8	2.4
Noncash or Part Noncash Acquisition, Investments Acquired	0.0	0.0	793.7
OG&E [Member]
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	426.4	439.5	360.0
Adjustments to reconcile net income to net cash provided from (used in) operating activities:
Depreciation and amortization	506.6	460.9	416.0
Deferred income taxes and other tax credits, net	15.4	220.5	44.6
Allowance for equity funds used during construction	(19.4)	(6.9)	(6.7)
Stock-based compensation expense	3.1	2.9	2.2
Regulatory assets	(92.1)	702.2	(874.9)
Regulatory liabilities	(12.2)	(9.1)	12.2
Other assets	4.7	0.0	(2.2)
Other liabilities	0.3	(5.6)	(11.2)
Change in certain current assets and liabilities:
Accounts receivable and accrued unbilled revenues, net	42.1	(96.6)	(3.0)
Fuel, materials and supplies inventories	(122.8)	(130.1)	(3.4)
Fuel recoveries	535.4	(363.0)	(180.5)
Other current assets	51.1	(30.1)	(21.4)
Accounts payable	(131.1)	135.8	(11.0)
Income taxes payable - parent	9.4	8.0	0.7
Other current liabilities	34.6	19.3	3.3
Net cash provided from (used in) operating activities	1,251.5	1,347.7	(275.3)
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures (less allowance for equity funds used during construction)	(1,178.2)	(1,050.9)	(778.5)
Cost of removal	(91.0)	(109.3)	(83.4)
Net cash used in investing activities	(1,269.2)	(1,160.2)	(861.9)
CASH FLOWS FROM FINANCING ACTIVITIES
Changes In advances with parent	229.2	(187.4)	372.5
Capital contribution from OGE Energy	0.0	0.0	530.0
Proceeds from long-term debt	788.8	0.0	499.8
Payment of long-term debt	(500.1)	(0.1)	(0.1)
Dividends paid on common stock	(500.0)	0.0	(265.0)
Net cash (used in) provided from financing activities	17.9	(187.5)	1,137.2
NET CHANGE IN CASH AND CASH EQUIVALENTS	0.2	0.0	0.0
CASH AND CASH EQUIVALENTS AT BEGINNING OF YEAR	0.0	0.0	0.0
CASH AND CASH EQUIVALENTS AT END OF YEAR	0.2	0.0	0.0
SUPPLEMENTAL CASH FLOW INFORMATION
Interest (net of interest capitalized)	180.7	154.6	148.9
Income taxes (net of income tax refunds)	44.2	(152.6)	(3.2)
NON-CASH INVESTING AND FINANCING ACTIVITIES
Power plant long-term service agreement	$ 0.7	$ 0.8	$ 2.4