Note A - Organization and Business (Details Textual)	6 Months Ended
Oct. 31, 2019
Number of Operating Subsidiaries	2
Number of Dealerships Operated	145

Number of operating subsidiaries that the entity has.

No definition available.

Name:	crmt_NumberOfOperatingSubsidiaries
Namespace Prefix:	crmt_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration