Consolidated Statements of Comprehensive Income (Loss) (Unaudited) (Parenthetical) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Mar. 31, 2025	Mar. 31, 2024	Mar. 31, 2025	Mar. 31, 2024
Statement of Comprehensive Income [Abstract]
Net of tax (provision) benefit	$ 3	$ 11	$ (1)	$ 12

Amount of tax expense (benefit) allocated to other comprehensive income (loss).

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+ Details