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Long-Term Debt and Short-Term Borrowings - Schedule of Long-Term Debt (Details) - USD ($) $ in Millions	Jun. 30, 2026	May 04, 2026	Dec. 31, 2025	Nov. 13, 2025	May 12, 2025	Feb. 23, 2024	Jun. 23, 2023	Mar. 18, 2021
Long-Term Debt
Total long-term debt	$ 5,871		$ 5,181
Less: current maturities of long-term debt	69		71
Less: unamortized discount	57		47
Less: unamortized debt issuance costs	14		13
Long-term debt, net of current maturities	5,731		5,050
Short-Term Borrowings
Warehouse lines of credit	711		1,609
Other	7		4
Total short-term borrowings	2,293		2,465
Warehouse agreement borrowings
Short-Term Borrowings
Warehouse lines of credit	711		1,609
Commercial paper
Short-Term Borrowings
Commercial paper program	$ 1,575		852
Interest rate	4.08%
Senior Secured Term Loans
Long-Term Debt
Total long-term debt	$ 1,266		1,325
Senior notes \| 5.500% senior notes due 2029
Long-Term Debt
Total long-term debt	500		500
Short-Term Borrowings
Interest rate						5.50%
Senior notes \| 4.800% senior notes due 2030
Long-Term Debt
Total long-term debt	600		600
Short-Term Borrowings
Interest rate					4.80%
Senior notes \| 2.500% senior notes due 2031
Long-Term Debt
Total long-term debt	500		500
Short-Term Borrowings
Interest rate								2.50%
Senior notes \| 4.900% senior notes due 2033
Long-Term Debt
Total long-term debt	750		750
Short-Term Borrowings
Interest rate				4.90%
Senior notes \| 5.950% senior notes due 2034
Long-Term Debt
Total long-term debt	1,000		1,000
Short-Term Borrowings
Interest rate							5.95%
Senior notes \| 5.500% senior notes due 2035
Long-Term Debt
Total long-term debt	500		500
Short-Term Borrowings
Interest rate					5.50%
Senior notes \| 5.250% senior notes due 2036
Long-Term Debt
Total long-term debt	750		0
Short-Term Borrowings
Interest rate		5.25%
Senior notes \| Other
Long-Term Debt
Total long-term debt	$ 5		$ 6