Investments (Narrative) (Detail) - USD ($) $ in Millions |
Sep. 30, 2026 |
Dec. 31, 2025 |
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| Atlantic Coast Pipeline | Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherLiabilitiesCurrent | ||
| Schedule of Equity Method Investments [Line Items] | ||
| Current liabilities | $ 2 | $ 4 |
| Dominion Privatization [Member] | Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherReceivablesNetCurrent | ||
| Schedule of Equity Method Investments [Line Items] | ||
| Loans receivable | 8 | 10 |
| Trading Securities | ||
| Schedule of Equity Method Investments [Line Items] | ||
| Rabbi trust securities | $ 201 | $ 181 |
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- Definition Loans receivable. No definition available.
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- Definition The total amount of cash and securities held by third party trustees pursuant to terms of debt instruments or other agreements as of the date of each statement of financial position presented, which can be used by the trustee only to pay the noncurrent portion of specified obligations. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount classified as liabilities attributable to disposal group held for sale or disposed of, expected to be disposed of within one year or the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition 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. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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