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Debt - Senior Notes (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended	9 Months Ended
Debt - Senior Notes (Details) - USD ($) $ in Millions	Oct. 31, 2026	Sep. 30, 2026	Sep. 30, 2026	Sep. 30, 2025
Debt Instrument [Line Items]
Senior note debt repurchases through repurchase program			$ 1,872	$ 1,708
Senior Notes
Debt Instrument [Line Items]
Debt instrument, repurchased face amount			1,837
Debt instrument, repurchased face amount		$ 1,847	1,847
Senior Notes due December 2027 \| Senior Notes
Debt Instrument [Line Items]
Debt instrument, repurchased face amount		500	1,647
Gain (loss) on repurchase of debt instrument		(2)	(7)
Debt debt premium and issuance costs		(2)	(7)
Senior Notes due December 2027 \| Senior Notes \| Subsequent Event
Debt Instrument [Line Items]
Debt instrument, repurchased face amount	$ 569
Senior note debt repurchases through repurchase program	$ 569
Senior Notes due July 2028 \| Senior Notes
Debt Instrument [Line Items]
Debt instrument, repurchased face amount		58	200
Gain (loss) on repurchase of debt instrument		3	9
Debt debt premium and issuance costs			(1)
Senior note debt repurchases through repurchase program		$ 55	$ 190