Debt - Scheduled Remaining Maturity of Long-term Debt (Details) - USD ($) $ in Millions	Mar. 31, 2025	Dec. 31, 2024
Debt Instrument [Line Items]
2025	$ 3,772
2026	2,222
2027	2,930
2028	1,167
2029	947
2030 and thereafter	5,427
Total long-term debt	16,465	$ 17,495
Unsecured debt
Debt Instrument [Line Items]
2025	1,900
2026	69
2027	1,528
2028	767
2029	906
2030 and thereafter	5,408
Total long-term debt	10,578	11,062
Secured debt
Debt Instrument [Line Items]
Total long-term debt	5,887	$ 6,433
Long-term debt \| Unsecured debt
Debt Instrument [Line Items]
2025	1,956
2026	151
2027	1,622
2028	874
2029	1,029
2030 and thereafter	5,691
Total long-term debt	11,323
Long-term debt \| Secured debt
Debt Instrument [Line Items]
2025	1,872
2026	2,153
2027	1,402
2028	400
2029	41
2030 and thereafter	19
Total long-term debt	5,887
Original issue discount \| Unsecured debt
Debt Instrument [Line Items]
Debt instrument, unamortized discount	(745)
Original issue discount \| Unsecured debt \| 2025
Debt Instrument [Line Items]
Debt instrument, unamortized discount, current	(56)
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)

Long-Term Debt, Maturity, After Year Four

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