Significant Accounting Policies (Checks the Outstanding Accounts Payable but not yet Presented for Payment and Recorded) (Detail) - USD ($) $ in Millions		Dec. 31, 2023	Dec. 31, 2022
Accounts Payable [Line Items]
Accounts payable for checks outstanding	[1]	$ 54	$ 35
Virginia Electric and Power Company
Accounts Payable [Line Items]
Accounts payable for checks outstanding		$ 44	$ 21

[1] In addition, at December 31, 2023 and 2022, Dominion Energy had $19 million and $14 million, respectively, of checks outstanding but not yet presented for payment included in current liabilities held for sale.