Variable Interest Entities (Narrative) (Detail) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2024
Variable Interest Entity [Line Items]
Payable to affiliates	[1]	$ 2,220		$ 2,291	[2]
Virginia Electric and Power Company
Variable Interest Entity [Line Items]
Payable to affiliates	[3]	1,613		$ 1,688	[4]
Virginia Electric and Power Company | CVOW Commercial Project
Variable Interest Entity [Line Items]
Equity Method Investment, Ownership Percentage				50.00%
Variable Interest Entity Not Primary Beneficiary | Virginia Electric and Power Company | DES
Variable Interest Entity [Line Items]
Shared Services Purchased		155	$ 115
Variable Interest Entity Not Primary Beneficiary | Virginia Electric and Power Company | DES | Related Party
Variable Interest Entity [Line Items]
Payable to affiliates		51		$ 38
Variable Interest Entity Not Primary Beneficiary | OSWP [Member]
Variable Interest Entity [Line Items]
Payable to affiliates		$ 6		$ 0

[1] See Note 10 for amounts attributable to related parties.

[2] Dominion Energy’s Consolidated Balance Sheet at December 31, 2024 has been derived from the audited Consolidated Balance Sheet at that date.

[3] See Note 19 for amounts attributable to affiliates.

[4] Virginia Power’s Consolidated Balance Sheet at December 31, 2024 has been derived from the audited Consolidated Balance Sheet at that date.