Organization and Business - Additional Information (Details)	3 Months Ended	9 Months Ended
Jan. 31, 2026 dealership	Jan. 31, 2026 dealership subsidiary
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of operating subsidiaries \| subsidiary		2
Number of dealerships operated		136
Number of dealerships closed	18

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