Additional number of common shares reserved for future issuance.

No definition available.

Name:	crmt_CommonStockAdditionalCapitalSharesReservedForFutureIssuance
Namespace Prefix:	crmt_
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Period Type:	instant

- Definition

Unrecognized cost of not currently expected to vest share-based compensation awards.

+ References

No definition available.

+ Details

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- Definition

Represents the number of options exercised through net settlements during the period in accordance with plan provisions.

+ References

No definition available.

+ Details

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- Definition

Represents the number of options exercised through net settlements during the period in accordance with plan provisions, net of shares to satisfy the exercise price and applicable withholding taxes.

+ References

No definition available.

+ Details

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- Definition

The grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ References

No definition available.

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Period Type:	duration

- Definition

With regard to stock options, this element represents the reduction in shares issued during the period to satisfy the exercise price and applicable withholding taxes.

+ References

No definition available.

+ Details

Name:	crmt_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsReductionInSharesIssuedToSatisfyTheExercisePriceAndApplicableWithholdingTaxes
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- Definition

As of the balance sheet date, the number of shares into which not currently expected to vest stock options outstanding can be converted under the option plan.

+ References

No definition available.

+ Details

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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-Subparagraph (b)
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-Subparagraph (h)(1)(i)
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- Definition

The amount of expense, net of income tax, recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

No definition available.

+ Details

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- Definition

Aggregate number of common shares reserved for future issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29)
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- Definition

Unrecognized cost of unvested share-based compensation awards.

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-Publisher FASB
-Name Accounting Standards Codification
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-Subparagraph (i)
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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-Subparagraph (c)(2)(iii)(1)
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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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-Publisher FASB
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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 2
-Subparagraph (a)(3)
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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

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Period Type:	instant

- Definition

Gross number of share options (or share units) granted during the period.

+ References

No definition available.

+ Details

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- Definition

Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

+ References

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Number of options outstanding, including both vested and non-vested options.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)-(ii)
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- Definition

Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest exercisable or convertible options. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (e)(2)
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- Definition

Number of fully vested and expected to vest exercisable options that may be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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-Paragraph 2
-Subparagraph (e)(2)
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- Definition

Weighted-average exercise price, at which grantee can acquire shares reserved for issuance, for fully vested and expected to vest exercisable or convertible options. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 2
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Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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Period Type:	duration

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Weighted average remaining contractual term for fully vested and expected to vest exercisable or convertible options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (e)(2)
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- Definition

Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
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Note K - Stock-based Compensation Plans (Details Textual) - USD ($)		12 Months Ended
	Aug. 05, 2015	Apr. 30, 2017	Apr. 30, 2016	Apr. 30, 2015	Apr. 30, 2014	Oct. 14, 2009	Oct. 13, 2009
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross		45,000	338,750	89,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value		$ 8,700,000	$ 4,800,000
Share-based Compensation Arrangement by Share-based Payment Award, Options Exercised Through Net Settlements		88,750
Share-based Compensation Arrangement by Share-based Payment Award, Options, Reduction in Shares Issued to Satisfy the Exercise Price and Applicable Withholding Taxes		68,397
Share-based Compensation Arrangement by Share-based Payment Award, Options Exercised Through Net Settlements, Net of Shares to Satisfy the Exercise Price and Applicable Withholding Taxes		20,353
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Number		669,500
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Aggregate Intrinsic Value		$ 8,200,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Weighted Average Remaining Contractual Term		3 years 40 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Weighted Average Exercise Price		$ 26.17
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number		1,028,500	1,278,250	981,750	1,117,000
Allocated Share-based Compensation Expense		$ 1,300,000	$ 1,500,000	$ 780,000
Allocated Share-based Compensation Expense, Net of Tax		$ 811,000	952,000	489,000
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period		3 years
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period		5 years
Employee Stock Option [Member]
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized		$ 2,800,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition		2 years 328 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Grant Date Fair Value		$ 461,000	5,600,000	1,400,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross		45,000
Allocated Share-based Compensation Expense		$ 1,200,000	1,400,000	664,000
Allocated Share-based Compensation Expense, Net of Tax		728,000	$ 870,000	$ 416,000
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross			131,125
Employee Service Share-based Compensation, Not Currently Expected to Vest Awards, Compensation Cost Not yet Recognized		$ 1,100,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Not Currently Expected to Vest, Outstanding, Number		62,750
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number		131,125
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period			5 years
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period		10,000	0	9,500
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value		$ 39.14		$ 52.10
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant		170,027
Restated Option Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant		277,500
Common Stock, Additional Capital Shares Reserved for Future Issuance	300,000
Common Stock, Capital Shares Reserved for Future Issuance	1,800,000
Restated Option Plan [Member] \| Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period	10 years
Stock Incentive Plan [Member]
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized		$ 557,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition		4 years
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized						300,000	150,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value		$ 763,000	$ 495,000	$ 495,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period		10,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value		$ 39.14
Allocated Share-based Compensation Expense		$ 107,000	99,000	90,000
Allocated Share-based Compensation Expense, Net of Tax		$ 67,000	$ 62,000	$ 56,000