Consolidated Statements of Comprehensive Income (Unaudited) (Parenthetical) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Net deferred gains (losses) on derivative-hedging activities, tax	$ 5	$ (37)
Changes in unrealized net gains (losses) on investment securities, tax	(6)	4
Net derivative (gains) losses-hedging activities, tax	10	(3)
Net pension and other postretirement benefit costs, tax	(14)	(1)
Virginia Electric and Power Company
Net deferred gains (losses) on derivative-hedging activities, tax	2	(2)
Changes in unrealized net gains (losses) on investment securities, tax	(1)	1
Dominion Energy Gas Holdings, LLC
Net deferred gains (losses) on derivative-hedging activities, tax	9	(4)
Net derivative (gains) losses-hedging activities, tax	(1)	1
Net pension and other postretirement benefit costs, tax	$ (1)	$ (1)

Amount, before reclassification, of tax expense (benefit) for gain (loss) from derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=114867106&loc=d3e640-108580

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Amount of tax expense (benefit) for reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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Amount of tax (expense) benefit for reclassification adjustment from accumulated other comprehensive (income) loss of defined benefit plan.

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-SubTopic 10
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Amount of tax expense (benefit) before reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities.

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