Derivatives and Hedge Accounting Activities (Schedule of Offsetting Assets) (Parenthetical) (Detail) - USD ($) $ in Millions	Sep. 30, 2026	Dec. 31, 2025
Offsetting Assets [Line Items]
Derivative assets, not subject to a master netting or similar arrangement	$ 350	$ 217
Virginia Electric and Power Company
Offsetting Assets [Line Items]
Derivative assets, not subject to a master netting or similar arrangement	$ 9	$ 18

Fair value of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, not subject to a master netting arrangement.

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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+ Details