Allowance for Credit Losses - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Finance Receivables, Net [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Ending balance: Collectively evaluated for impairment	$ 74,433	$ 71,012
Finance Receivables, Net [Member] | Retail and Commercial Loan [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Impaired finance receivables aggregated and collectively evaluated for impairment	253	231
Finance Receivables, Net [Member] | Dealer Products [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Ending balance: Collectively evaluated for impairment	17,345	17,073
Finance Receivables, Net [Member] | TMNA [Member] | Financial Guarantee [Member] | Dealer Products [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Ending balance: Collectively evaluated for impairment	1,047	1,091
Finance Receivables, Net [Member] | Private Toyota Distributors [Member] | Financial Guarantee [Member] | Dealer Products [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Ending balance: Collectively evaluated for impairment	140	$ 132
COVID-19 [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Additional provision for credit losses	$ 264