Variable Interest Entities - (Narrative) (Detail) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Variable Interest Entity [Line Items]
Payable to affiliates	[1]	$ 2,093		$ 2,078	[2]
Regulatory assets-current	[3]	1,092		1,309	[2]
Other current assets	[3]	1,018		1,158	[2]
Regulatory assets-noncurrent	[3]	7,859		8,356	[2]
Securities due within one year	[3]	2,344		6,589	[2]
Accrued interest, payroll and taxes	[3]	1,286		1,075	[2]
Long-term debt		35,064		33,248	[2]
Virginia Electric and Power Company
Variable Interest Entity [Line Items]
Payable to affiliates	[4]	1,437		1,529	[5]
Regulatory assets-current	[6]	744		868	[5]
Other current assets	[4],[6]	297		375	[5]
Regulatory assets-noncurrent	[6]	4,352		4,317	[5]
Securities due within one year	[6]	100		381	[5]
Accrued interest, payroll and taxes	[6]	414		293	[5]
Long-term debt		19,335		17,115	[5]
Variable Interest Entity Not Primary Beneficiary | Virginia Electric and Power Company
Variable Interest Entity [Line Items]
Regulatory assets-current		100
Other current assets		6
Regulatory assets-noncurrent		1,200
Securities due within one year		65
Accrued interest, payroll and taxes		8
Long-term debt		1,200
Variable Interest Entity Not Primary Beneficiary | Virginia Electric and Power Company | DES
Variable Interest Entity [Line Items]
Shared Services Purchased		115	$ 113
Variable Interest Entity Not Primary Beneficiary | Virginia Electric and Power Company | DES | Related Party
Variable Interest Entity [Line Items]
Payable to affiliates		$ 33		$ 32

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

[2] Dominion Energy’s Consolidated Balance Sheet at December 31, 2023 has been derived from the audited Consolidated Balance Sheet at that date.

[3] See Note 15 for amounts attributable to VIEs.

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

[5] Virginia Power’s Consolidated Balance Sheet at December 31, 2023 has been derived from the audited Consolidated Balance Sheet at that date.

[6] See Note 15 for amounts attributable to VIEs.