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Fair Value Measurements - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024	Dec. 31, 2024
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Investments in unconsolidated affiliates	$ 1,071		$ 1,071		$ 1,506
Revolving Credit Facility \| Line of Credit
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Maximum borrowing capacity	6,000		6,000
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	410		410
Long-term debt	52		52
Carrying value
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Total debt	27,800		27,800		23,900
Level 2 \| Fair value
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Total debt	27,500		27,500		23,200
Lending Joint Ventures
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Investments in unconsolidated affiliates	66		66		49
Financial Guarantee
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Carrying value of non-contingent liability	493		493
Financial Guarantee \| Lending Joint Ventures
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Carrying value of non-contingent liability	17		17		$ 21
Other (expense) income	$ 4	$ 5	$ 9	$ 9