Debt under Vehicle Programs and Borrowing Arrangements - Schedule Of Contractual Maturities (Detail) - Vehicle Programs $ in Millions	Dec. 31, 2024 USD ($)
Debt Instrument [Line Items]
2025	$ 1,966
2026	6,484
2027	3,930
2028	2,330
2029	2,749
Thereafter	154
Total	17,613
Bank And Bank-Sponsored Facilities
Debt Instrument [Line Items]
2025	500
2026	3,200
2027	100
2029	$ 100
Short-term debt, weighted average interest rate, at point in time	4.04%

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