Consolidated Statements of Comprehensive Income (Loss) (Unaudited) (Parenthetical) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Statement of Comprehensive Income [Abstract]
Net of tax (provision) benefit	$ 4	$ (1)	$ 3	$ 11

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

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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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+ Details