Allowance for Credit Losses - Past Due Finance Receivables and Investments in Operating Leases (Details) - USD ($) $ in Millions	Sep. 30, 2018	Mar. 31, 2018
Past Due Finance Receivables and Investments in Operating Leases
Finance receivables	$ 269	$ 223
Investments in operating leases	120	106
Total	$ 389	$ 329

Aggregate amount of financing and leases receivables that are equal to or greater than 60 days past due.

No definition available.

Name:	tmcc_FinancingAndLeasesReceivableEqualToGreaterThan60DaysPastDue
Namespace Prefix:	tmcc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant