Goodwill and Identifiable Intangible Assets and Liabilities - Narrative (Details) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2026	Dec. 31, 2025
Goodwill [Line Items]
Goodwill	$ 2,810	$ 2,810
Retail Reporting Unit
Goodwill [Line Items]
Goodwill	2,688	2,688
Goodwill, expected tax deductible amount	$ 1,944
Business acquisition, goodwill, expected tax deductible term	15 years
Texas Generation Reporting Unit
Goodwill [Line Items]
Goodwill	$ 122	$ 122

Amount, after accumulated impairment loss, of asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.

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+ Details

- 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.

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+ Details