Share-Based Compensation Expense (Details) - USD ($) shares in Thousands, $ in Millions		12 Months Ended
		Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Share-Based Compensation Expense [Abstract]
Granted (in shares)		395	421	411
Compensation cost for share-based awards	[1]	$ 36	$ 31	$ 73
Tax benefit recognized in income		9	8	$ 19
Unrecognized compensation cost related to nonvested share-based compensation awards		$ 37	$ 28
Weighted-average period for recognition of unrecognized compensation cost related to nonvested share-based compensation awards (in years)		1 year 9 months 18 days
Service-based awards [Member]
Share-Based Compensation Expense [Abstract]
Granted (in shares)		200

[1] Compensation costs for share-based payments are included in O&M expense. Amount for equity awards (non-cash) amounted to $20 million in 2022.