Earnings Per Share (Calculation of Basic and Diluted EPS) (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions		3 Months Ended
		Mar. 31, 2024	Mar. 31, 2023
Earnings Per Share [Abstract]
Net income attributable to Dominion Energy from continuing operations		$ 560	$ 700
Preferred stock dividends (see Note 16)		(20)	(20)
Net income attributable to Dominion Energy from continuing operations - Basic		540	680
Net income attributable to Dominion Energy from continuing operations - Diluted		540	680
Net income (loss) attributable to Dominion Energy		$ 114	$ 281
Average shares of common stock outstanding – Basic		837.6	835.2
Net effect of dilutive securities	[1]	0.0	0.3
Average shares of common stock outstanding – Diluted		837.6	835.5
EPS from continuing operations – Basic		$ 0.64	$ 0.81
EPS from discontinued operations – Basic		0.14	0.34
Net income attributable to Dominion Energy		0.78	1.15
EPS from continuing operations – Diluted		0.64	0.81
EPS from discontinued operations – Diluted		0.14	0.34
Net income attributable to Dominion Energy		$ 0.78	$ 1.15

[1] Dilutive securities for the three months ended March 31, 2023 include stock potentially to be issued to satisfy the obligation under a settlement agreement with the SCDOR (applying the if converted method). See Note 17 for additional information.