XML 72 R59.htm IDEA: XBRL DOCUMENT
v3.19.2

Other Income (Narrative) (Details) | 6 Months Ended
--- | ---
Jun. 30, 2019 USD ($)
Other Income and Expenses [Abstract] |
Payment Holdback Percentage | 50.00%
One-time enrollment fee in program | $ 9,850

X
- Definition Payment Holdback Percentage + References No definition available. + Details
Name: | cacc_PaymentHoldbackPercentage
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
- References No definition available. + Details
Name: | us-gaap_OtherIncomeAndExpensesAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration