Consolidated Statements of Comprehensive Income (Loss) (Unaudited) (Parenthetical) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Statement of Comprehensive Income [Abstract]
Net of tax (provision) benefit	$ (7)	$ 4	$ (9)	$ 3

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

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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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+ Details