Transfers of Receivables - Assets and Liabilities of Securitizations (Details) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019	Jun. 30, 2019
Securitization Transactions [Line Items]
Cash and cash equivalents	$ 12,838	$ 9,067
Finance Receivables and Net Investment In Operating Leases, After Allowance for Credit Losses	130,303		$ 143,479
Related Debt	135,267	140,029
Variable Interest Entity, Primary Beneficiary [Member]
Securitization Transactions [Line Items]
Cash and cash equivalents	3,204	3,202
Related Debt	45,908	50,865
Variable Interest Entity, Primary Beneficiary [Member] | Securitization Transactions [Member]
Securitization Transactions [Line Items]
Cash and cash equivalents	3,200	3,200
Finance Receivables and Net Investment in Operating Leases, Before Allowance for Credit Losses	64,700	73,600
Allowance for Credit Losses	400	200
Finance Receivables and Net Investment In Operating Leases, After Allowance for Credit Losses	64,300	73,400
Related Debt	45,900	50,900
Variable Interest Entity, Primary Beneficiary [Member] | Securitization Transactions [Member] | Financing Receivable [Member]
Securitization Transactions [Line Items]
Cash and cash equivalents	2,500	2,700
Finance Receivables and Net Investment in Operating Leases, Before Allowance for Credit Losses	50,200	58,700
Allowance for Credit Losses	400	200
Finance Receivables and Net Investment In Operating Leases, After Allowance for Credit Losses	49,800	58,500
Related Debt	36,600	41,400
Variable Interest Entity, Primary Beneficiary [Member] | Securitization Transactions [Member] | Retail [Member]
Securitization Transactions [Line Items]
Cash and cash equivalents	1,800	1,800
Finance Receivables and Net Investment in Operating Leases, Before Allowance for Credit Losses	33,000	32,600
Allowance for Credit Losses	400	200
Finance Receivables and Net Investment In Operating Leases, After Allowance for Credit Losses	32,600	32,400
Related Debt	26,200	28,000
Variable Interest Entity, Primary Beneficiary [Member] | Securitization Transactions [Member] | Wholesale [Member]
Securitization Transactions [Line Items]
Cash and cash equivalents	700	900
Finance Receivables and Net Investment in Operating Leases, Before Allowance for Credit Losses	17,200	26,100
Allowance for Credit Losses	0	0
Finance Receivables and Net Investment In Operating Leases, After Allowance for Credit Losses	17,200	26,100
Related Debt	10,400	13,400
Variable Interest Entity, Primary Beneficiary [Member] | Securitization Transactions [Member] | Net Investment in Operating Leases [Member]
Securitization Transactions [Line Items]
Cash and cash equivalents	700	500
Finance Receivables and Net Investment in Operating Leases, Before Allowance for Credit Losses	14,500	14,900
Allowance for Credit Losses	0	0
Finance Receivables and Net Investment In Operating Leases, After Allowance for Credit Losses	14,500	14,900
Related Debt	9,300	9,500
Consolidated Entity Excluding Variable Interest Entities (VIE) [Member] | Securitization Transactions [Member]
Securitization Transactions [Line Items]
Cash and cash equivalents	400	300
Finance Receivables and Net Investment in Operating Leases, Before Allowance for Credit Losses	9,700	6,400
Allowance for Credit Losses	100	0
Finance Receivables and Net Investment In Operating Leases, After Allowance for Credit Losses	9,600	6,400
Related Debt	8,600	5,700
Consolidated Entity Excluding Variable Interest Entities (VIE) [Member] | Securitization Transactions [Member] | Financing Receivable [Member]
Securitization Transactions [Line Items]
Cash and cash equivalents	400	300
Finance Receivables and Net Investment in Operating Leases, Before Allowance for Credit Losses	9,700	6,400
Allowance for Credit Losses	100	0
Finance Receivables and Net Investment In Operating Leases, After Allowance for Credit Losses	9,600	6,400
Related Debt	8,600	5,700
Consolidated Entity Excluding Variable Interest Entities (VIE) [Member] | Securitization Transactions [Member] | Retail [Member]
Securitization Transactions [Line Items]
Cash and cash equivalents	400	300
Finance Receivables and Net Investment in Operating Leases, Before Allowance for Credit Losses	9,100	5,700
Allowance for Credit Losses	100	0
Finance Receivables and Net Investment In Operating Leases, After Allowance for Credit Losses	9,000	5,700
Related Debt	8,300	5,100
Consolidated Entity Excluding Variable Interest Entities (VIE) [Member] | Securitization Transactions [Member] | Wholesale [Member]
Securitization Transactions [Line Items]
Cash and cash equivalents	0	0
Finance Receivables and Net Investment in Operating Leases, Before Allowance for Credit Losses	600	700
Allowance for Credit Losses	0	0
Finance Receivables and Net Investment In Operating Leases, After Allowance for Credit Losses	600	700
Related Debt	300	600
Consolidated Entity Excluding Variable Interest Entities (VIE) [Member] | Securitization Transactions [Member] | Net Investment in Operating Leases [Member]
Securitization Transactions [Line Items]
Cash and cash equivalents	0	0
Finance Receivables and Net Investment in Operating Leases, Before Allowance for Credit Losses	0	0
Allowance for Credit Losses	0	0
Finance Receivables and Net Investment In Operating Leases, After Allowance for Credit Losses	0	0
Related Debt	0	0
Consolidated Entities [Member] | Securitization Transactions [Member]
Securitization Transactions [Line Items]
Cash and cash equivalents	3,600	3,500
Finance Receivables and Net Investment in Operating Leases, Before Allowance for Credit Losses	74,400	80,000
Allowance for Credit Losses	500	200
Finance Receivables and Net Investment In Operating Leases, After Allowance for Credit Losses	73,900	79,800
Related Debt	54,500	56,600
Consolidated Entities [Member] | Securitization Transactions [Member] | Financing Receivable [Member]
Securitization Transactions [Line Items]
Cash and cash equivalents	2,900	3,000
Finance Receivables and Net Investment in Operating Leases, Before Allowance for Credit Losses	59,900	65,100
Allowance for Credit Losses	500	200
Finance Receivables and Net Investment In Operating Leases, After Allowance for Credit Losses	59,400	64,900
Related Debt	45,200	47,100
Consolidated Entities [Member] | Securitization Transactions [Member] | Retail [Member]
Securitization Transactions [Line Items]
Cash and cash equivalents	2,200	2,100
Finance Receivables and Net Investment in Operating Leases, Before Allowance for Credit Losses	42,100	38,300
Allowance for Credit Losses	500	200
Finance Receivables and Net Investment In Operating Leases, After Allowance for Credit Losses	41,600	38,100
Related Debt	34,500	33,100
Consolidated Entities [Member] | Securitization Transactions [Member] | Wholesale [Member]
Securitization Transactions [Line Items]
Cash and cash equivalents	700	900
Finance Receivables and Net Investment in Operating Leases, Before Allowance for Credit Losses	17,800	26,800
Allowance for Credit Losses	0	0
Finance Receivables and Net Investment In Operating Leases, After Allowance for Credit Losses	17,800	26,800
Related Debt	10,700	14,000
Consolidated Entities [Member] | Securitization Transactions [Member] | Net Investment in Operating Leases [Member]
Securitization Transactions [Line Items]
Cash and cash equivalents	700	500
Finance Receivables and Net Investment in Operating Leases, Before Allowance for Credit Losses	14,500	14,900
Allowance for Credit Losses	0	0
Finance Receivables and Net Investment In Operating Leases, After Allowance for Credit Losses	14,500	14,900
Related Debt	$ 9,300	$ 9,500