Goodwill and Intangible Assets (Goodwill By Reportable Operating Segment) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Goodwill [Line Items]
Goodwill, gross	$ 19,425,000,000	$ 19,425,000,000
Accumulated impairment charges	(122,000,000)	(122,000,000)
Goodwill, net	19,303,000,000	19,303,000,000
Impairment charges	0
Electric Utilities and Infrastructure
Goodwill [Line Items]
Goodwill, gross	17,379,000,000	17,379,000,000
Goodwill, net	17,379,000,000	17,379,000,000
Gas Utilities and Infrastructure
Goodwill [Line Items]
Goodwill, gross	1,924,000,000	1,924,000,000
Goodwill, net	1,924,000,000	1,924,000,000
Commercial Renewables
Goodwill [Line Items]
Goodwill, gross	122,000,000	122,000,000
Accumulated impairment charges	$ (122,000,000)	$ (122,000,000)