Debt - Scheduled Remaining Maturity of Long-term Debt (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Debt Instrument [Line Items]
Long-term debt, maturities, repayments of principal in year one	$ 4,818
Long-term debt, maturities, repayments of principal in year two	2,228
Long-term debt, maturities, repayments of principal in year three	2,935
Long-term debt, maturities, repayments of principal in year four	1,157
Long-term debt, maturities, repayments of principal in year five	945
Long-term debt, maturities, repayments of principal after year five	5,412
Total long-term debt	17,495	$ 17,570
Unsecured debt
Debt Instrument [Line Items]
Long-term debt, maturities, repayments of principal in year one	2,408
Long-term debt, maturities, repayments of principal in year two	69
Long-term debt, maturities, repayments of principal in year three	1,528
Long-term debt, maturities, repayments of principal in year four	758
Long-term debt, maturities, repayments of principal in year five	906
Long-term debt, maturities, repayments of principal after year five	5,393
Total long-term debt	11,062	10,424
Secured debt
Debt Instrument [Line Items]
Total long-term debt	6,433	$ 7,146
Long-term debt | Unsecured debt
Debt Instrument [Line Items]
Long-term debt, maturities, repayments of principal in year one	2,482
Long-term debt, maturities, repayments of principal in year two	151
Long-term debt, maturities, repayments of principal in year three	1,622
Long-term debt, maturities, repayments of principal in year four	865
Long-term debt, maturities, repayments of principal in year five	1,029
Long-term debt, maturities, repayments of principal after year five	5,676
Total long-term debt	11,825
Long-term debt | Secured debt
Debt Instrument [Line Items]
Long-term debt, maturities, repayments of principal in year one	2,410
Long-term debt, maturities, repayments of principal in year two	2,159
Long-term debt, maturities, repayments of principal in year three	1,407
Long-term debt, maturities, repayments of principal in year four	399
Long-term debt, maturities, repayments of principal in year five	39
Long-term debt, maturities, repayments of principal after year five	19
Total long-term debt	6,433
Original issue discount | Unsecured debt
Debt Instrument [Line Items]
Debt instrument, unamortized discount	(763)
Original issue discount | Unsecured debt | 2025
Debt Instrument [Line Items]
Debt instrument, unamortized discount, current	(74)
Original issue discount | Unsecured debt | 2026
Debt Instrument [Line Items]
Debt instrument, unamortized discount, noncurrent	(82)
Original issue discount | Unsecured debt | 2027
Debt Instrument [Line Items]
Debt instrument, unamortized discount, noncurrent	(94)
Original issue discount | Unsecured debt | 2028
Debt Instrument [Line Items]
Debt instrument, unamortized discount, noncurrent	(107)
Original issue discount | Unsecured debt | 2029
Debt Instrument [Line Items]
Debt instrument, unamortized discount, noncurrent	(123)
Original issue discount | Unsecured debt | 2030 and thereafter
Debt Instrument [Line Items]
Debt instrument, unamortized discount, noncurrent	$ (283)