Finance Receivables - Contractual Maturities (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Finance Receivables Maturity [Abstract]
Financing Receivable, Gross	$ 113,705,000,000	$ 101,358,000,000
Finance receivables before unearned interest supplements	7,793,000,000	6,765,000,000
Financing Receivable, Allowance for Credit Losses, Write-downs	405,000,000	279,000,000
Consumer Segment [Member]
Finance Receivables Maturity [Abstract]
Financing Receivable, Gross	78,392,000,000	71,503,000,000
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	2,424,000,000	2,640,000,000
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	7,562,000,000	6,265,000,000
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	11,497,000,000	14,091,000,000
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	20,536,000,000	18,579,000,000
Financing Receivable, Year One, Originated, Current Fiscal Year	35,426,000,000	28,986,000,000
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	947,000,000	942,000,000
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year, Writeoff	75,000,000
Financing Receivable, Allowance for Credit Losses, Write-downs	401,000,000	278,000,000
Financing Receivable, Originated, More than Five Years before Current Fiscal Year, Writeoff	47,000,000
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year, Writeoff	40,000,000
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year, Writeoff	85,000,000
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year, Writeoff	117,000,000
Financing Receivable, Year One, Originated, Current Fiscal Year, Writeoff	37,000,000
Consumer Segment [Member] | Percent of Total
Finance Receivables Maturity [Abstract]
Financing Receivable, Gross	1.000	1.000
Consumer Segment [Member] | 31-60 Days Past Due [Member]
Finance Receivables Maturity [Abstract]
Financing Receivable, Gross	690,000,000	649,000,000
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	49,000,000	60,000,000
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	130,000,000	91,000,000
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	125,000,000	181,000,000
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	187,000,000	150,000,000
Financing Receivable, Year One, Originated, Current Fiscal Year	159,000,000	126,000,000
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	40,000,000	41,000,000
Consumer Segment [Member] | 31-60 Days Past Due [Member] | Percent of Total
Finance Receivables Maturity [Abstract]
Financing Receivable, Gross	0.009	0.009
Consumer Segment [Member] | Financing Receivables, 61-120 Days past due [Member]
Finance Receivables Maturity [Abstract]
Financing Receivable, Gross	195,000,000	149,000,000
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	11,000,000	12,000,000
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	30,000,000	20,000,000
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	37,000,000	39,000,000
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	58,000,000	40,000,000
Financing Receivable, Year One, Originated, Current Fiscal Year	50,000,000	29,000,000
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	9,000,000	9,000,000
Consumer Segment [Member] | Financing Receivables, 61-120 Days past due [Member] | Percent of Total
Finance Receivables Maturity [Abstract]
Financing Receivable, Gross	0.002	0.002
Consumer Segment [Member] | Greater Than 120 Days Past Due [Member]
Finance Receivables Maturity [Abstract]
Financing Receivable, Gross	43,000,000	38,000,000
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	4,000,000	4,000,000
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	7,000,000	5,000,000
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	10,000,000	7,000,000
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	10,000,000	7,000,000
Financing Receivable, Year One, Originated, Current Fiscal Year	5,000,000	6,000,000
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	7,000,000	9,000,000
Consumer Segment [Member] | Greater Than 120 Days Past Due [Member] | Percent of Total
Finance Receivables Maturity [Abstract]
Financing Receivable, Gross	0.001	0.001
Consumer Segment [Member] | Total past due [Member]
Finance Receivables Maturity [Abstract]
Financing Receivable, Gross	928,000,000	836,000,000
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	64,000,000	76,000,000
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	167,000,000	116,000,000
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	172,000,000	227,000,000
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	255,000,000	197,000,000
Financing Receivable, Year One, Originated, Current Fiscal Year	214,000,000	161,000,000
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	56,000,000	59,000,000
Consumer Segment [Member] | Total past due [Member] | Percent of Total
Finance Receivables Maturity [Abstract]
Financing Receivable, Gross	0.012	0.012
Consumer Segment [Member] | Financial Asset, 1 to 29 Days Past Due [Member]
Finance Receivables Maturity [Abstract]
Financing Receivable, Gross	77,464,000,000	70,667,000,000
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	2,360,000,000	2,564,000,000
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	7,395,000,000	6,149,000,000
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	11,325,000,000	13,864,000,000
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	20,281,000,000	18,382,000,000
Financing Receivable, Year One, Originated, Current Fiscal Year	35,212,000,000	28,825,000,000
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	891,000,000	883,000,000
Consumer Segment [Member] | Financial Asset, 1 to 29 Days Past Due [Member] | Percent of Total
Finance Receivables Maturity [Abstract]
Financing Receivable, Gross	0.988	0.988
Consumer Segment [Member] | Retail [Member]
Finance Receivables Maturity [Abstract]
Financing Receivable, Gross	78,392,000,000	71,503,000,000
Finance receivables before unearned interest supplements	81,736,000,000	73,808,000,000
Non-Consumer Segment [Member]
Finance Receivables Maturity [Abstract]
Financing Receivable, Gross	35,313,000,000	29,855,000,000
Financing Receivable, Allowance for Credit Losses, Write-downs	4,000,000	1,000,000
Non-Consumer Segment [Member] | Wholesale and Dealer Loans [Member]
Finance Receivables Maturity [Abstract]
Financing Receivable, Gross	33,377,000,000	28,408,000,000
Non-Consumer Segment [Member] | Other Finance Receivables [Member]
Finance Receivables Maturity [Abstract]
Financing Receivable, Gross	$ 1,936,000,000	$ 1,447,000,000