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Fair Value Measurements - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Aug. 12, 2025	Dec. 31, 2024
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Investments in unconsolidated affiliates	$ 1,084		$ 1,084			$ 1,506
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	83		83
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	404		404
Long-term debt	21		21
Carrying value
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Total debt	28,200		28,200			23,900
Level 2 \| Fair value
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Total debt	28,000		28,000			23,200
Lending Joint Ventures
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Investments in unconsolidated affiliates	94		94			49
Financial Guarantee
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Carrying value of non-contingent liability	487		487
Financial Guarantee \| Lending Joint Ventures
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Carrying value of non-contingent liability	14		14			$ 21
Other (expense) income	$ 5	$ 4	$ 14	$ 13