Impact of Derivative Activities on Income (Details) - Not Designated as Hedging Instrument - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Derivative [Line Items]
Derivative Instruments Gain (Loss) Reclassified To Regulatory Assets And Liabilities Net		$ (1)	$ (1)	$ (1)
Pre-tax gains (losses) reclassified into income during the period from regulatory assets and (liabilities)		0	0	1
Derivative, Gain (Loss) on Derivative, Net		(2)	(1)	(1)
Natural Gas Commodity Contract
Derivative [Line Items]
Derivative Instruments Gain (Loss) Reclassified To Regulatory Assets And Liabilities Net		(1)	(1)	(1)
Pre-tax gains (losses) reclassified into income during the period from regulatory assets and (liabilities)		0	0	(1)
Derivative, Gain (Loss) on Derivative, Net	[1]	$ (2)	$ (1)	$ (1)

[1] Recorded to cost of natural gas sold and transported. These losses are subject to cost-recovery mechanisms and reclassified out of income to a regulatory asset, as appropriate.