Finance Receivables - Credit Quality and Impaired Receivables (Details) - USD ($)	3 Months Ended
	Mar. 31, 2022	Dec. 31, 2021
Financing Receivable, Credit Quality Indicator [Line Items]
Non-Accrual of Revenue	90
Financing Receivables	$ 93,876,000,000	$ 93,275,000,000
Wholesale and Dealer Loans [Member] | Financing Receivable [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivables	13,000,000	62,000,000
Commercial Portfolio Segment [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivables	21,797,000,000	19,730,000,000
Financing Receivable, Revolving	18,947,000,000	16,944,000,000
Commercial Portfolio Segment [Member] | Group I
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivables	16,718,000,000	14,779,000,000
Financing Receivable, Revolving	15,628,000,000	13,670,000,000
Commercial Portfolio Segment [Member] | Group I | Percent of Total
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivables	0.829	0.812
Commercial Portfolio Segment [Member] | Group II
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivables	2,944,000,000	2,793,000,000
Financing Receivable, Revolving	2,845,000,000	2,689,000,000
Commercial Portfolio Segment [Member] | Group II | Percent of Total
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivables	0.146	0.153
Commercial Portfolio Segment [Member] | Group III
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivables	447,000,000	559,000,000
Financing Receivable, Revolving	423,000,000	529,000,000
Commercial Portfolio Segment [Member] | Group III | Percent of Total
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivables	0.022	0.031
Commercial Portfolio Segment [Member] | Group IV
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivables	61,000,000	66,000,000
Financing Receivable, Revolving	51,000,000	56,000,000
Commercial Portfolio Segment [Member] | Group IV | Percent of Total
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivables	0.003	0.004
Commercial Portfolio Segment [Member] | Dealer Loan
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	490,000,000	410,000,000
Financing Receivable, Originated Four Years before Latest Fiscal Year	186,000,000	75,000,000
Financing Receivable, Originated Three Years before Latest Fiscal Year	45,000,000	182,000,000
Financing Receivable, Originated Two Years before Latest Fiscal Year	84,000,000	47,000,000
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	252,000,000	114,000,000
Financing Receivable, Originated in Current Fiscal Year	166,000,000	425,000,000
Financing Receivable Originations Total	1,223,000,000	1,253,000,000
Commercial Portfolio Segment [Member] | Dealer Loan | Group I
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	470,000,000	391,000,000
Financing Receivable, Originated Four Years before Latest Fiscal Year	155,000,000	68,000,000
Financing Receivable, Originated Three Years before Latest Fiscal Year	44,000,000	151,000,000
Financing Receivable, Originated Two Years before Latest Fiscal Year	78,000,000	45,000,000
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	232,000,000	109,000,000
Financing Receivable, Originated in Current Fiscal Year	111,000,000	345,000,000
Financing Receivable Originations Total	1,090,000,000	1,109,000,000
Commercial Portfolio Segment [Member] | Dealer Loan | Group II
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	12,000,000	11,000,000
Financing Receivable, Originated Four Years before Latest Fiscal Year	26,000,000	7,000,000
Financing Receivable, Originated Three Years before Latest Fiscal Year	1,000,000	26,000,000
Financing Receivable, Originated Two Years before Latest Fiscal Year	5,000,000	2,000,000
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	13,000,000	4,000,000
Financing Receivable, Originated in Current Fiscal Year	42,000,000	54,000,000
Financing Receivable Originations Total	99,000,000	104,000,000
Commercial Portfolio Segment [Member] | Dealer Loan | Group III
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	8,000,000	8,000,000
Financing Receivable, Originated Four Years before Latest Fiscal Year	0	0
Financing Receivable, Originated Three Years before Latest Fiscal Year	0	1,000,000
Financing Receivable, Originated Two Years before Latest Fiscal Year	0	0
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	5,000,000	1,000,000
Financing Receivable, Originated in Current Fiscal Year	11,000,000	20,000,000
Financing Receivable Originations Total	24,000,000	30,000,000
Commercial Portfolio Segment [Member] | Dealer Loan | Group IV
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	0	0
Financing Receivable, Originated Four Years before Latest Fiscal Year	5,000,000	0
Financing Receivable, Originated Three Years before Latest Fiscal Year	0	4,000,000
Financing Receivable, Originated Two Years before Latest Fiscal Year	1,000,000	0
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	2,000,000	0
Financing Receivable, Originated in Current Fiscal Year	2,000,000	6,000,000
Financing Receivable Originations Total	10,000,000	10,000,000
Commercial Portfolio Segment [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivables	20,170,000,000	18,197,000,000
Commercial Portfolio Segment [Member] | Commercial Portfolio Segment [Member] | Percent of Total
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivables	1.000	1.000
Commercial Portfolio Segment [Member] | Wholesale and Dealer Loans [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivables	20,170,000,000	18,197,000,000
Consumer Portfolio Segment [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivables	72,079,000,000	73,545,000,000
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	2,667,000,000	868,000,000
Financing Receivable, Originated Four Years before Latest Fiscal Year	5,466,000,000	2,676,000,000
Financing Receivable, Originated Three Years before Latest Fiscal Year	11,039,000,000	6,692,000,000
Financing Receivable, Originated Two Years before Latest Fiscal Year	20,582,000,000	12,875,000,000
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	25,461,000,000	22,967,000,000
Financing Receivable, Originated in Current Fiscal Year	6,864,000,000	27,467,000,000
Consumer Portfolio Segment [Member] | Financing Receivables, 31-60 Days Past Due [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivables	600,000,000	586,000,000
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	76,000,000	39,000,000
Financing Receivable, Originated Four Years before Latest Fiscal Year	84,000,000	52,000,000
Financing Receivable, Originated Three Years before Latest Fiscal Year	116,000,000	98,000,000
Financing Receivable, Originated Two Years before Latest Fiscal Year	192,000,000	120,000,000
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	123,000,000	186,000,000
Financing Receivable, Originated in Current Fiscal Year	9,000,000	91,000,000
Consumer Portfolio Segment [Member] | Financing Receivables, 61-120 Days past due [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivables	105,000,000	127,000,000
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	11,000,000	7,000,000
Financing Receivable, Originated Four Years before Latest Fiscal Year	16,000,000	10,000,000
Financing Receivable, Originated Three Years before Latest Fiscal Year	20,000,000	20,000,000
Financing Receivable, Originated Two Years before Latest Fiscal Year	31,000,000	29,000,000
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	26,000,000	40,000,000
Financing Receivable, Originated in Current Fiscal Year	1,000,000	21,000,000
Consumer Portfolio Segment [Member] | Financing Receivables, Greater Than 120 Days Past Due [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivables	43,000,000	43,000,000
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	15,000,000	10,000,000
Financing Receivable, Originated Four Years before Latest Fiscal Year	6,000,000	6,000,000
Financing Receivable, Originated Three Years before Latest Fiscal Year	8,000,000	6,000,000
Financing Receivable, Originated Two Years before Latest Fiscal Year	13,000,000	9,000,000
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	1,000,000	11,000,000
Financing Receivable, Originated in Current Fiscal Year	0	1,000,000
Consumer Portfolio Segment [Member] | Total past due [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivables	748,000,000	756,000,000
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	102,000,000	56,000,000
Financing Receivable, Originated Four Years before Latest Fiscal Year	106,000,000	68,000,000
Financing Receivable, Originated Three Years before Latest Fiscal Year	144,000,000	124,000,000
Financing Receivable, Originated Two Years before Latest Fiscal Year	236,000,000	158,000,000
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	150,000,000	237,000,000
Financing Receivable, Originated in Current Fiscal Year	10,000,000	113,000,000
Consumer Portfolio Segment [Member] | Financial Asset, 1 to 29 Days Past Due [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivables	71,331,000,000	72,789,000,000
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	2,565,000,000	812,000,000
Financing Receivable, Originated Four Years before Latest Fiscal Year	5,360,000,000	2,608,000,000
Financing Receivable, Originated Three Years before Latest Fiscal Year	10,895,000,000	6,568,000,000
Financing Receivable, Originated Two Years before Latest Fiscal Year	20,346,000,000	12,717,000,000
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	25,311,000,000	22,730,000,000
Financing Receivable, Originated in Current Fiscal Year	6,854,000,000	27,354,000,000
Consumer Portfolio Segment [Member] | Percent of Total
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivables	1.000	1.000
Consumer Portfolio Segment [Member] | Percent of Total | Financing Receivables, 31-60 Days Past Due [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivables	0.008	0.008
Consumer Portfolio Segment [Member] | Percent of Total | Financing Receivables, 61-120 Days past due [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivables	0.002	0.002
Consumer Portfolio Segment [Member] | Percent of Total | Financing Receivables, Greater Than 120 Days Past Due [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivables	0	0
Consumer Portfolio Segment [Member] | Percent of Total | Total past due [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivables	0.010	0.010
Consumer Portfolio Segment [Member] | Percent of Total | Financial Asset, 1 to 29 Days Past Due [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivables	$ 0.990	$ 0.990
Consumer Portfolio Segment [Member] | Pass [Member] | Maximum [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Finance Receivables Credit Quality Ratings Term Range	60 days
Consumer Portfolio Segment [Member] | Substandard [Member] | Minimum [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Finance Receivables Credit Quality Ratings Term Range	120 days
Consumer Portfolio Segment [Member] | Special Mention [Member] | Maximum [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Finance Receivables Credit Quality Ratings Term Range	120 days
Consumer Portfolio Segment [Member] | Special Mention [Member] | Minimum [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Finance Receivables Credit Quality Ratings Term Range	61 days