Consolidated Statements of Comprehensive Income (Unaudited) (Parenthetical) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Net deferred gain (losses) on derivative-hedging activities, tax	$ 5	$ (4)	$ (8)	$ 89
Changes in unrealized net gains (losses) on investment securities, tax	(2)	(6)	8	(10)
Changes in net unrecognized pension and other postretirement benefit costs, tax	(3)	3	(7)	3
Net derivative (gains) losses-hedging activities, tax	(4)	(2)	(8)	(9)
Net realized (gains) losses on investment securities, tax	1	0	1	4
Net pension and other postretirement benefit costs, tax	(9)	(8)	(16)	(13)
Virginia Electric and Power Company
Net deferred gain (losses) on derivative-hedging activities, tax	5	(1)	(6)	15
Changes in unrealized net gains (losses) on investment securities, tax	0	(1)	0	(1)
Net derivative (gains) losses-hedging activities, tax	0	(1)	0	(1)
Net realized (gains) losses on investment securities, tax	$ 0	$ 2	$ 0	$ 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.

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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, before reclassification adjustment, of tax (expense) benefit for (increase) decrease in accumulated other comprehensive income for defined benefit plan.

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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

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Amount, before adjustment, of tax expense (benefit) for unrealized holding gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Excludes tax expense (benefit) for unrealized gain (loss) on investment in debt security measured at amortized cost (held-to-maturity) from transfer to available-for-sale.

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