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Finance Receivables - Schedule of Finance Receivables, Net (Details) - USD ($) $ in Millions	Jun. 30, 2025	Mar. 31, 2025	Dec. 31, 2024	Jun. 30, 2024	Mar. 31, 2024	Dec. 31, 2023
Accounts, Notes, Loans and Financing Receivable [Line Items]
Less: allowance for loan losses	$ (2,720)		$ (2,458)
Total finance receivables, net	91,840		93,510
Level 2
Accounts, Notes, Loans and Financing Receivable [Line Items]
Fair value utilizing inputs	16,633		19,843
Level 3
Accounts, Notes, Loans and Financing Receivable [Line Items]
Fair value utilizing inputs	76,842		74,729
Retail finance receivables
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables	77,837		76,066	$ 73,335
Less: allowance for loan losses	(2,630)	$ (2,479)	(2,400)	$ (2,261)	$ (2,320)	$ (2,308)
Total finance receivables, net	75,207		73,667
Commercial finance receivables
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables	16,723		19,901
Less: allowance for loan losses	(91)		(58)
Total finance receivables, net	16,633		19,843
Dealer cash management balances	3,200		3,400
Commercial finance receivables \| Dealer Financing
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables	16,152		18,902
Commercial finance receivables \| Other Financing
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables	$ 571		$ 999