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Namespace Prefix:	crmt_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

The maximum borrowing base allowed expressed as a percentage of financing receivables balance under the covenant of the debt instrument.

No definition available.

Name:	crmt_DebtInstrumentCovenantMaximumBorrowingBasePercentageOfFinancingReceivables
Namespace Prefix:	crmt_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

The maximum amount of real estate that is allowed to be disposed of under the covenant of the debt instrument.

No definition available.

Name:	crmt_DebtInstrumentCovenantMaximumDisposalOfRealEstate
Namespace Prefix:	crmt_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

The maximum amount of other properties that can be disposed of under the covenant of the debt instrument.

No definition available.

Name:	crmt_DebtInstrumentCovenantMaximumDisposalOtherProperties
Namespace Prefix:	crmt_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

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

No definition available.

Name:	crmt_FinancingReceivablePaymentPeriod
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Balance Type:	na
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Additional borrowing capacity of line of credit facility with an accordion feature.

No definition available.

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Namespace Prefix:	crmt_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Represents increase in maximum borrowing capacity for line of credit.

No definition available.

Name:	crmt_LineOfCreditFacilityIncreaseInMaximumBorrowingCapacity
Namespace Prefix:	crmt_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Amount of increase under the credit facility.

No definition available.

Name:	crmt_LineOfCreditFacilityTotalIncreaseInBorrowingCapacity
Namespace Prefix:	crmt_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Percentage of unused line, categorized as a fee, contingent upon amendment terms.

No definition available.

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Namespace Prefix:	crmt_
Data Type:	dtr-types:percentItemType
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Period Type:	instant

Amount of capital expenditures allowable under Credit Facilities in the aggregate during any fiscal year.

No definition available.

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

Minimum percent of pool balance.

No definition available.

Name:	crmt_MinimumPercentOfPoolBalance
Namespace Prefix:	crmt_
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Period Type:	instant

Percentage of weighted average fixed coupon rate of notes payable issued.

No definition available.

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Namespace Prefix:	crmt_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

Amount of amortization expense attributable to debt discount (premium) and debt issuance costs.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

No definition available.

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
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Period Type:	duration

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Period Type:	instant

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Period Type:	instant

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

No definition available.

Name:	us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
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Namespace Prefix:
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Balance Type:
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Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=crmt_MediumtermVehicleContractsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=crmt_LongtermVehicleContractsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
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Balance Type:
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Namespace Prefix:
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Balance Type:
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Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_LineOfCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	us-gaap_CreditFacilityAxis=us-gaap_RevolvingCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Namespace Prefix:
Data Type:	na
Balance Type:
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Namespace Prefix:
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