XML 51 R36.htm IDEA: XBRL DOCUMENT
v2.4.0.8

Description Of Business (Narrative) (Details) (USD $) | 3 Months Ended
--- | ---
Mar. 31, 2014 loan item
Description Of Business [Abstract] |
Number of consumers required to group advances | 100
Number of consumer loans assigned to receive accelerated Dealer Holdback payment | 100
Servicing fee percentage in collections | 20.00%
Number of business programs | 2
One-time enrollment fee in program | $ 9,850
Percentage of enrollment fee of first accelerated dealer holdback payment | 50.00%

X
- Details
Name: | cacc_DescriptionOfBusinessAbstract
Namespace Prefix: | cacc_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number Of Business Programs + References No definition available. + Details
Name: | cacc_NumberOfBusinessPrograms
Namespace Prefix: | cacc_
Data Type: | xbrli:positiveIntegerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number Of Consumer Loans Assigned To Receive Accelerated Dealer Holdback Payment + References No definition available. + Details
Name: | cacc_NumberOfConsumerLoansAssignedToReceiveAcceleratedDealerHoldbackPayment
Namespace Prefix: | cacc_
Data Type: | xbrli:positiveIntegerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number Of Consumers Required To Group Advances + References No definition available. + Details
Name: | cacc_NumberOfConsumersRequiredToGroupAdvances
Namespace Prefix: | cacc_
Data Type: | xbrli:positiveIntegerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage Of Revenue From Enrollment And Registration Fees In Program + References No definition available. + Details
Name: | cacc_PercentageOfRevenueFromEnrollmentAndRegistrationFeesInProgram
Namespace Prefix: | cacc_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Revenue From Enrollment And Registration Fees In Program + References No definition available. + Details
Name: | cacc_RevenueFromEnrollmentAndRegistrationFeesInProgram
Namespace Prefix: | cacc_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Service fee income as a percentage of collections. + References No definition available. + Details
Name: | cacc_ServiceFeeIncomeAsPercentageOfCollections
Namespace Prefix: | cacc_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration