Acquisitions and Dispositions (Schedule of Capital Expenditures and Significant Noncash Items Reported As Discontinued Operations) (Detail) - USD ($) $ in Millions		6 Months Ended
		Jun. 30, 2022	Jun. 30, 2021
Significant noncash items:
Accrued capital expenditures	[1]	$ 512	$ 327
Dominion Energy Gas Holdings, LLC | Q-Pipe Group
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Capital expenditures			15
Significant noncash items:
Accrued capital expenditures			$ 4

[1] See Note 16 for noncash financing activities related to the remarketing of Series A Preferred Stock and the issuance of common stock associated with the settlement of litigation.