Financial Risk Management Activities - Schedule of Derivative Transactions Designated and Effective as Cash Flow Hedges (Details) - Parent Company [Member] - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Amount of Pre-Tax Gain (Loss) Recognized in AOCL on Derivatives	$ 5	$ (27)
Amount of Pre-Tax Gain (Loss) Reclassified from AOCL into Income	1	1
Interest Rate Swap [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Amount of Pre-Tax Gain (Loss) Recognized in AOCL on Derivatives	5	(27)
Amount of Pre-Tax Gain (Loss) Reclassified from AOCL into Income	$ 1	$ 1

- 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.

+ References + Details