Variable Interest Entities - (Narrative) (Detail) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Variable Interest Entity [Line Items]
Payable to affiliates	[1]	$ 2,101		$ 2,101		$ 2,078	[2]
Regulatory assets-current	[3]	969		969		1,309	[2]
Other current assets	[3]	1,284		1,284		1,158	[2]
Regulatory assets-noncurrent	[3]	8,349		8,349		8,356	[2]
Securities due within one year	[3]	1,800		1,800		6,589	[2]
Accrued interest, payroll and taxes	[3]	861		861		1,075	[2]
Long-term debt		36,617		36,617		33,248	[2]
Virginia Electric and Power Company
Variable Interest Entity [Line Items]
Payable to affiliates		1,369		1,369		1,285	[4]
Regulatory assets-current	[5]	662		662		868	[4]
Other current assets	[5],[6]	444		444		375	[4]
Regulatory assets-noncurrent	[5]	4,593		4,593		4,317	[4]
Securities due within one year	[5]	531		531		381	[4]
Accrued interest, payroll and taxes	[5]	356		356		293	[4]
Long-term debt		18,908		18,908		17,115	[4]
Variable Interest Entity Not Primary Beneficiary | Virginia Electric and Power Company
Variable Interest Entity [Line Items]
Regulatory assets-current		121		121
Other current assets		40		40
Regulatory assets-noncurrent		1,100		1,100
Securities due within one year		146		146
Accrued interest, payroll and taxes		24		24
Long-term debt		1,100		1,100
Variable Interest Entity Not Primary Beneficiary | Virginia Electric and Power Company | DES
Variable Interest Entity [Line Items]
Shared Services Purchased		128	$ 113	243	$ 226
Variable Interest Entity Not Primary Beneficiary | Virginia Electric and Power Company | DES | Related Party
Variable Interest Entity [Line Items]
Payable to affiliates		$ 32		$ 32		$ 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] Virginia Power’s Consolidated Balance Sheet at December 31, 2023 has been derived from the audited Consolidated Balance Sheet at that date.

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

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