Finance Receivables, Net - Additional Information (Details) $ in Millions	Sep. 30, 2020 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable accrued interest before allowance for credit loss	$ 202
Retail Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable accrued interest before allowance for credit loss	168
Dealer Products [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable accrued interest before allowance for credit loss	$ 34