Finance Receivables, Net - Net Financing Receivables (Details) - USD ($) $ in Millions	Jun. 30, 2022	Mar. 31, 2022
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross finance receivables	$ 86,070	$ 83,678
Allowance for credit losses	(1,248)	(1,246)
Finance receivables, net	84,822	82,432
Finance Receivables, Net [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross finance receivables	85,761	83,450
Deferred origination costs	1,364	1,330
Deferred income	(1,055)	(1,102)
Allowance for credit losses	(1,248)	(1,246)
Finance receivables, net	84,822	82,432
Finance Receivables, Net [Member] | Retail receivables [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross finance receivables	75,178	73,152
Allowance for credit losses	(1,209)	(1,195)
Finance Receivables, Net [Member] | Dealer financing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross finance receivables	10,583	10,298
Allowance for credit losses	$ (39)	$ (51)