Other Income, Net (Components of Other Income, Net) (Detail) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2023	Mar. 31, 2022
Income Statement [Abstract]
Other income		$ 2	$ 2
Other expense		(2)	1
Gains on sales of assets	[1]	10	0
Allowance for equity funds used during construction		0	1
Other income, net		$ 10	$ 4

[1] Includes amounts recognized in connection with the transfer of property to satisfy litigation. See Note 10 for additional information.