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Fair Value Measurements - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 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	$ 1,031		$ 1,031		$ 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	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	388		388
Long-term debt	36		36
Carrying value
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Total debt	25,500		25,500		26,900
Level 2 \| Fair value
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Total debt	25,000		25,000		26,400
Lending Joint Ventures
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Investments in unconsolidated affiliates	90		90		88
Financial Guarantee
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Carrying value of non-contingent liability	471		471
Financial Guarantee \| Lending Joint Ventures
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Carrying value of non-contingent liability	7		7		$ 12
Other (expense) income	$ 3	$ 4	$ 7	$ 9