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Fair Value Measurements - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025	Dec. 31, 2025	Aug. 12, 2025
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Investments in unconsolidated affiliates	$ 1,122		$ 1,122		$ 1,046
Revolving Credit Facility \| Line of Credit
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Maximum borrowing capacity						$ 8,000
Revolving Credit Facility \| Variable-Rate Revolving Credit Facilities Due April 2027 \| Line of Credit \| Lending Joint Ventures
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Maximum borrowing capacity	43		43
Term Loan Facilities \| Variable-Rate Term Loan Facilities Due April 2027 \| Line of Credit \| Lending Joint Ventures
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Maximum borrowing capacity	219		219
Long-term debt	29		29
Carrying value
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Total debt	24,600		24,600		26,900
Level 2 \| Fair value
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Total debt	23,600		23,600		26,400
Lending Joint Ventures
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Investments in unconsolidated affiliates	96		96		88
Financial Guarantee
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Carrying value of non-contingent liability	262		262
Financial Guarantee \| Lending Joint Ventures
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Carrying value of non-contingent liability	2		2		$ 12
Other (expense) income	$ 6	$ 5	$ 14	$ 14