Note C - Finance Receivables (Details)	6 Months Ended
Oct. 31, 2014	Oct. 31, 2013
Note C - Finance Receivables (Details) [Line Items]
Installment Sale Contracts,Weighted Average Interest Rate	14.90%
Finance Receivables, Number of Loan Classes	1
Finance Receivables, Number of Risk Pools	1
Net Charge Offs as Percentage of Average Financing Receivables	13.40%	13.10%
Collections as Percentage of Average Financing Receivables	28.20%	27.30%
Delinquecies Greater Than 30 Days as Percentage of Average Financing Receivables	4.40%	4.70%
Minimum [Member]
Note C - Finance Receivables (Details) [Line Items]
Financing Receivable Interest Rate	11.00%
Financing Receivable Payment Period	18 months
Maximum [Member]
Note C - Finance Receivables (Details) [Line Items]
Financing Receivable Interest Rate	19.00%
Financing Receivable Payment Period	36 years

Represents the percentage of average financing receivables collected during the reported period.

No definition available.

Name:	crmt_CollectionsAsPercentageOfAverageFinancingReceivables
Namespace Prefix:	crmt_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Represents delinquencies greater than 30 days as a percentage of financing receivables.

No definition available.

Name:	crmt_DelinqueciesGreaterThan30DaysAsPercentageOfAverageFinancingReceivables
Namespace Prefix:	crmt_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

Represents the number of loan classes.

No definition available.

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

Represents the number of risk pools.

No definition available.

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

Represents the interest rate on installment sale contracts.

No definition available.

Name:	crmt_FinancingReceivableInterestRate
Namespace Prefix:	crmt_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Represents the payment period on installment sale contracts from the sale of used vehicles.

No definition available.

Name:	crmt_FinancingReceivablePaymentPeriod
Namespace Prefix:	crmt_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Represents the weighted average interest rate on installment sale contracts.

No definition available.

Name:	crmt_InstallmentSaleContractsWeightedAverageInterestRate
Namespace Prefix:	crmt_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Represents the percentage of average financing receivables charged off.

No definition available.

Name:	crmt_NetChargeOffsAsPercentageOfAverageFinancingReceivables
Namespace Prefix:	crmt_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Name:	crmt_NoteCFinanceReceivablesDetailsLineItems
Namespace Prefix:	crmt_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration