Leases (Summary of Total Lease Cost) (Detail) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Finance lease cost:
Finance lease cost, Amortization	[1]	$ 50	$ 41	$ 40
Finance lease cost, Interest	[2]	13	3	(3)
Operating lease cost	[3]	70	53	66
Short-term lease cost	[4]	32	31	32
Variable lease cost		6	4	5
Total lease cost		171	132	140
Virginia Electric and Power Company
Finance lease cost:
Finance lease cost, Amortization	[1]	24	15	12
Finance lease cost, Interest	[2]	4	3	1
Operating lease cost	[3]	43	32	30
Short-term lease cost	[4]	23	21	19
Variable lease cost		2	1	1
Total lease cost		$ 96	$ 72	$ 63

[1] Dominion Energy includes $3 million for each of the years ended December 31, 2023, 2022 and 2021 reflected in discontinued operations in its Consolidated Statements of Income.

[2] Dominion Energy includes $1 million for both the years ended December 31, 2023 and 2022 and less than $1 million for the year ended December 31, 2021 reflected in discontinued operations in its Consolidated Statements of Income.

[3] Dominion Energy includes $5 million, $6 million and $8 million for the years ended December 31, 2023, 2022 and 2021, respectively, reflected in discontinued operations in its Consolidated Statements of Income.

[4] Dominion Energy includes $2 million for each of the years ended December 31, 2023, 2022 and 2021 reflected in discontinued operations in its Consolidated Statements of Income.