Investment in Unconsolidated Affiliate (Tables)

12 Months Ended

Dec. 31, 2022

Equity Method Investments and Joint Ventures [Abstract]

Summarized Balance Sheet Financial Information for Equity Method Investment

The following tables present summarized unaudited financial information for 100 percent of Enable as of December 2, 2021 and for the period of January 1, 2021 through December 2, 2021 and the year ended December 31, 2020.

Balance Sheet	December 2, 2021
(In millions)
Current assets	$	594
Non-current assets	$	11,227
Current liabilities	$	1,254
Non-current liabilities	$	3,281

Summarized Income Statement Financial Information for Equity Method Investment

	Period of
Income Statement	January 1, 2021 through December 2, 2021		Year Ended December 31, 2020
(In millions)
Total revenues	$	3,466	$	2,463
Cost of natural gas and NGLs (excluding depreciation and amortization)	$	1,959	$	965
Operating income	$	634	$	465
Net income	$	461	$	52

Reconciliation of Equity in Earnings (Losses) of Unconsolidated Affiliates

The following table presents a reconciliation of OGE Energy's equity in earnings (losses) of unconsolidated affiliates for the period of January 1, 2021 through December 2, 2021 and the year ended December 31, 2020.

	Period of
(In millions)	January 1, 2021 through December 2, 2021			Year Ended December 31, 2020
Enable net income	$	461.0		$	52.0
Differences due to timing of OGE Energy and Enable accounting close		9.0			—
Enable net income used to calculate OGE Energy's equity in earnings	$	470.0		$	52.0
OGE Energy's percent ownership at period end		25.5	%		25.5	%
OGE Energy's portion of Enable net income	$	119.8		$	13.2
Amortization of basis difference and dilution recognition (A)		50.0			98.8
Impairment of OGE Energy's equity method investment in Enable (B)		—			(780.0	)
Equity in earnings (losses) of unconsolidated affiliates (C)	$	169.8		$	(668.0	)

(A)Includes loss on dilution, net of proportional basis difference recognition.

(B)During the year ended December 31, 2020, OGE Energy recorded a $780.0 million impairment on its investment in Enable as, effective March 31, 2020, OGE estimated the fair value of its investment in Enable was below the book value and concluded the decline in value was not temporary.

(C)For the year ended December 31, 2020, Enable recorded a $225.0 million impairment on an equity method investment, which ran through OGE Energy's portion of Enable net income and was offset by basis differences that flow through the amortization of basis difference and dilution recognition line item above.

Schedule of Related Party Transactions [Table Text Block]

The following table presents summarized related party transactions between OG&E and Enable during the period of January 1, 2021 through December 2, 2021 and the year ended December 31, 2020.

	Period of
(In millions)	January 1, 2021 through December 2, 2021			Year Ended December 31, 2020
Operating revenues:
Electricity to power electric compression assets	$	13.3		$	15.1
Fuel, purchased power and direct transmission expense:
Natural gas transportation services	$	32.7		$	32.8
Natural gas purchases (sales)	$	(33.5	)	$	2.7