Transfers of Receivables - Assets and Liabilities of Securitizations (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Securitization Transactions [Line Items]
Cash and Cash Equivalents, at Carrying Value	$ 14,349	$ 9,067
Finance Receivables and Net Investment In Operating Leases, After Allowance for Credit Losses	131,725	141,976	$ 146,263
Debt	137,677	140,029
Cash Contribution Collateral to Support Wholesale Securitization Program		0
Required pool balance	14,100	18,400
Adjusted Pool Balance	2,300	8,400
Variable Interest Entity, Primary Beneficiary [Member]
Securitization Transactions [Line Items]
Cash and Cash Equivalents, at Carrying Value	2,822	3,202
Debt	46,770	50,865
Cash Collateral to Support Wholesale Transactions	25	0
Variable Interest Entity, Primary Beneficiary [Member] | Maximum [Member]
Securitization Transactions [Line Items]
Cash Contribution Collateral to Support Wholesale Securitization Program	524
Variable Interest Entity, Primary Beneficiary [Member] | Minimum [Member]
Securitization Transactions [Line Items]
Cash Contribution Collateral to Support Wholesale Securitization Program	0
Variable Interest Entity, Primary Beneficiary [Member] | Securitization Transactions [Member]
Securitization Transactions [Line Items]
Cash and Cash Equivalents, at Carrying Value	2,800	3,200
Finance Receivables and Net Investment in Operating Leases, Before Allowance for Credit Losses	64,700	73,600
Financing and Loans and Leases Receivable Allowance	400	200
Finance Receivables and Net Investment In Operating Leases, After Allowance for Credit Losses	64,300	73,400
Debt	46,800	50,900
Variable Interest Entity, Primary Beneficiary [Member] | Securitization Transactions [Member] | Retail [Member]
Securitization Transactions [Line Items]
Cash and Cash Equivalents, at Carrying Value	2,000	1,800
Finance Receivables and Net Investment in Operating Leases, Before Allowance for Credit Losses	35,800	32,600
Financing and Loans and Leases Receivable Allowance	400	200
Finance Receivables and Net Investment In Operating Leases, After Allowance for Credit Losses	35,400	32,400
Debt	28,400	28,000
Variable Interest Entity, Primary Beneficiary [Member] | Securitization Transactions [Member] | Wholesale [Member]
Securitization Transactions [Line Items]
Cash and Cash Equivalents, at Carrying Value	200	900
Finance Receivables and Net Investment in Operating Leases, Before Allowance for Credit Losses	16,100	26,100
Financing and Loans and Leases Receivable Allowance	0	0
Finance Receivables and Net Investment In Operating Leases, After Allowance for Credit Losses	16,100	26,100
Debt	10,700	13,400
Variable Interest Entity, Primary Beneficiary [Member] | Securitization Transactions [Member] | Financing Receivable [Member]
Securitization Transactions [Line Items]
Cash and Cash Equivalents, at Carrying Value	2,200	2,700
Finance Receivables and Net Investment in Operating Leases, Before Allowance for Credit Losses	51,900	58,700
Financing and Loans and Leases Receivable Allowance	400	200
Finance Receivables and Net Investment In Operating Leases, After Allowance for Credit Losses	51,500	58,500
Debt	39,100	41,400
Variable Interest Entity, Primary Beneficiary [Member] | Securitization Transactions [Member] | Net Investment in Operating Leases [Member]
Securitization Transactions [Line Items]
Cash and Cash Equivalents, at Carrying Value	600	500
Finance Receivables and Net Investment in Operating Leases, Before Allowance for Credit Losses	12,800	14,900
Financing and Loans and Leases Receivable Allowance	0	0
Finance Receivables and Net Investment In Operating Leases, After Allowance for Credit Losses	12,800	14,900
Debt	7,700	9,500
Consolidated Entity Excluding Variable Interest Entities (VIE) [Member] | Securitization Transactions [Member]
Securitization Transactions [Line Items]
Cash and Cash Equivalents, at Carrying Value	400	300
Finance Receivables and Net Investment in Operating Leases, Before Allowance for Credit Losses	8,200	6,400
Financing and Loans and Leases Receivable Allowance	100	0
Finance Receivables and Net Investment In Operating Leases, After Allowance for Credit Losses	8,100	6,400
Debt	7,800	5,700
Consolidated Entity Excluding Variable Interest Entities (VIE) [Member] | Securitization Transactions [Member] | Retail [Member]
Securitization Transactions [Line Items]
Cash and Cash Equivalents, at Carrying Value	400	300
Finance Receivables and Net Investment in Operating Leases, Before Allowance for Credit Losses	7,900	5,700
Financing and Loans and Leases Receivable Allowance	100	0
Finance Receivables and Net Investment In Operating Leases, After Allowance for Credit Losses	7,800	5,700
Debt	7,600	5,100
Consolidated Entity Excluding Variable Interest Entities (VIE) [Member] | Securitization Transactions [Member] | Wholesale [Member]
Securitization Transactions [Line Items]
Cash and Cash Equivalents, at Carrying Value	0	0
Finance Receivables and Net Investment in Operating Leases, Before Allowance for Credit Losses	300	700
Financing and Loans and Leases Receivable Allowance	0	0
Finance Receivables and Net Investment In Operating Leases, After Allowance for Credit Losses	300	700
Debt	200	600
Consolidated Entity Excluding Variable Interest Entities (VIE) [Member] | Securitization Transactions [Member] | Financing Receivable [Member]
Securitization Transactions [Line Items]
Cash and Cash Equivalents, at Carrying Value	400	300
Finance Receivables and Net Investment in Operating Leases, Before Allowance for Credit Losses	8,200	6,400
Financing and Loans and Leases Receivable Allowance	100	0
Finance Receivables and Net Investment In Operating Leases, After Allowance for Credit Losses	8,100	6,400
Debt	7,800	5,700
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, at Carrying Value	0	0
Finance Receivables and Net Investment in Operating Leases, Before Allowance for Credit Losses	0	0
Financing and Loans and Leases Receivable Allowance	0	0
Finance Receivables and Net Investment In Operating Leases, After Allowance for Credit Losses	0	0
Debt	0	0
Consolidated Entities [Member] | Securitization Transactions [Member]
Securitization Transactions [Line Items]
Cash and Cash Equivalents, at Carrying Value	3,200	3,500
Finance Receivables and Net Investment in Operating Leases, Before Allowance for Credit Losses	72,900	80,000
Financing and Loans and Leases Receivable Allowance	500	200
Finance Receivables and Net Investment In Operating Leases, After Allowance for Credit Losses	72,400	79,800
Debt	54,600	56,600
Consolidated Entities [Member] | Securitization Transactions [Member] | Wholesale [Member]
Securitization Transactions [Line Items]
Finance Receivables and Net Investment In Operating Leases, After Allowance for Credit Losses	16,400	26,800
Consolidated Entities [Member] | Securitization Transactions [Member] | Retail [Member]
Securitization Transactions [Line Items]
Cash and Cash Equivalents, at Carrying Value	2,400	2,100
Finance Receivables and Net Investment in Operating Leases, Before Allowance for Credit Losses	43,700	38,300
Financing and Loans and Leases Receivable Allowance	500	200
Finance Receivables and Net Investment In Operating Leases, After Allowance for Credit Losses	43,200	38,100
Debt	36,000	33,100
Consolidated Entities [Member] | Securitization Transactions [Member] | Wholesale [Member]
Securitization Transactions [Line Items]
Cash and Cash Equivalents, at Carrying Value	200	900
Finance Receivables and Net Investment in Operating Leases, Before Allowance for Credit Losses	16,400	26,800
Financing and Loans and Leases Receivable Allowance	0	0
Finance Receivables and Net Investment In Operating Leases, After Allowance for Credit Losses	16,400	26,800
Debt	10,900	14,000
Consolidated Entities [Member] | Securitization Transactions [Member] | Financing Receivable [Member]
Securitization Transactions [Line Items]
Cash and Cash Equivalents, at Carrying Value	2,600	3,000
Finance Receivables and Net Investment in Operating Leases, Before Allowance for Credit Losses	60,100	65,100
Financing and Loans and Leases Receivable Allowance	500	200
Finance Receivables and Net Investment In Operating Leases, After Allowance for Credit Losses	59,600	64,900
Debt	46,900	47,100
Consolidated Entities [Member] | Securitization Transactions [Member] | Net Investment in Operating Leases [Member]
Securitization Transactions [Line Items]
Cash and Cash Equivalents, at Carrying Value	600	500
Finance Receivables and Net Investment in Operating Leases, Before Allowance for Credit Losses	12,800	14,900
Financing and Loans and Leases Receivable Allowance	0	0
Finance Receivables and Net Investment In Operating Leases, After Allowance for Credit Losses	12,800	14,900
Debt	$ 7,700	$ 9,500