Regulatory Assets and Liabilities, Regulatory Liabilities (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2022	Dec. 31, 2021
Regulatory Liabilities [Line Items]
Regulatory Liability, Current		$ 148	$ 54
Regulatory Liability, Noncurrent		715	709
Deferred Income Tax Adjustments and TCJA Refunds
Regulatory Liabilities [Line Items]
Regulatory Liability, Current	[1]	0	15	[2]
Regulatory Liability, Noncurrent	[1]	469	486	[2]
Plant Removal Costs
Regulatory Liabilities [Line Items]
Regulatory Liability, Current		0	0	[2]
Regulatory Liability, Noncurrent		198	190	[2]
Contract Valuation Adjustments
Regulatory Liabilities [Line Items]
Regulatory Liability, Current	[3]	119	27	[2]
Regulatory Liability, Noncurrent	[3]	$ 1	1	[2]
Contract Valuation Adjustments | Minimum [Member]
Regulatory Liabilities [Line Items]
Regulatory Liability, Amortization Period		1 year
Contract Valuation Adjustments | Maximum [Member]
Regulatory Liabilities [Line Items]
Regulatory Liability, Amortization Period		2 years
Other
Regulatory Liabilities [Line Items]
Regulatory Liability, Current		$ 19	6	[2]
Regulatory Liability, Noncurrent		5	2	[2]
Effect of regulation on employee benefit costs
Regulatory Liabilities [Line Items]
Regulatory Liability, Current		0	0	[2]
Regulatory Liability, Noncurrent		20	19	[2]
Renewable resources and environmental initiatives
Regulatory Liabilities [Line Items]
Regulatory Liability, Current		0	0	[2]
Regulatory Liability, Noncurrent		14	7	[2]
Formula rates
Regulatory Liabilities [Line Items]
Regulatory Liability, Current		10	6	[2]
Regulatory Liability, Noncurrent		$ 8	$ 4	[2]
Formula rates | Minimum [Member]
Regulatory Liabilities [Line Items]
Regulatory Liability, Amortization Period		1 year
Formula rates | Maximum [Member]
Regulatory Liabilities [Line Items]
Regulatory Liability, Amortization Period		2 years

[1] Includes the revaluation of recoverable/regulated plant accumulated deferred income taxes and revaluation impact of non-plant accumulated deferred income taxes due to the TCJA.

[2] Prior period amounts have been restated to conform with current year presentation.

[3] Includes the fair value of FTR instruments utilized/intended to offset the impacts of transmission system congestion.