Significant Accounting Policies - Schedule of Increase (Decrease) to Each Affected Line Item in Companies' Consolidated Financial Statements (Parenthetical) (Details) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended								12 Months Ended
		Dec. 31, 2024	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2024		Dec. 31, 2023		Dec. 31, 2022
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Increase (decrease) in net income from continuing operations		$ (27)	$ 6	$ (8)	$ (237)
increase (decrease) in earnings per share		$ (0.03)	$ (0.01)	$ (0.01)	$ (0.28)
Increase (decrease) in net income (loss) from discontinued operations		$ 0	$ (2)	$ 16	$ 4
Increase decrease in earnings per share from discontinued operations		$ 0	$ 0	$ 0.02	$ 0
Income tax expense										$ 308	[1]	$ 568	[2]	$ 59	[3]
Net income from continuing operations										1,927		2,156		269	[4]
Net income (loss) from discontinued operations										$ 197		$ (125)		$ 922	[4]
Earnings per share		$ 0.15	$ 1.12	$ 0.66	$ 0.50	$ 0.37	$ 0.16	$ 0.66	$ 1.14	$ 2.44		$ 2.33		$ 1.33	[4]
Impact on deferred income taxes												$ 10
Indirect Impacts
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Losses (gains) on sales of assets														$ (14)
Income tax expense														3
Net income from continuing operations														$ 11
Net income (loss) from discontinued operations										$ 18		$ 38
Earnings per share										$ 0.02		$ 0.04		$ 0.01
Virginia Power
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Income tax expense	[5]									$ 408		$ 389		$ 294

[1] The significant expense categories and amounts in the segment information presented above align with the segment-level information that is regularly provided to Dominion Energy’s CODM.

[2] The significant expense categories and amounts in the segment information presented above align with the segment-level information that is regularly provided to Dominion Energy’s CODM.

[3] The significant expense categories and amounts in the segment information presented above align with the segment-level information that is regularly provided to Dominion Energy’s CODM.

[4] As discussed in Note 19, effective in June 2022 through its redemption in September 2022, the Series A Preferred Stock was considered to be mandatorily redeemable and was classified in current liabilities.

[5] The significant expense categories and amounts in the segment information presented above align with the segment-level information that is regularly provided to Virginia Power’s CODM.