Variable Interest Entities - Additional Information (Details) - USD ($) $ in Millions	Dec. 31, 2018	Mar. 31, 2018
Variable Interest Entity Consolidated Carrying Amount Assets And Liabilities [Abstract]
Securities retained by TMCC	$ 1,425	$ 1,520

The amount of securities retained by the reporting entity in the consolidated Variable Interest Entity's debt obligations collateralized by finance receivables.

No definition available.

Name:	tmcc_VariableInterestEntityConsolidatedCarryingAmountSecuredDebtAmountRetainedByReportingEntity
Namespace Prefix:	tmcc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant