XML 34 R23.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Description of Business (Tables) | 3 Months Ended
--- | ---
Mar. 31, 2018
Description Of Business [Abstract] |
Percentage of Consumer Loans Assigned with FICO Score of Less Than 650 or No FICO Score | The following table shows the percentage of Consumer Loans assigned to us with either FICO® scores below 650 or no FICO® scores:
|  | For the Three Months Ended March 31,
Consumer Loan Assignment Volume |  | 2018 |  | 2017
Percentage of total unit volume with either FICO® scores below 650 or no FICO® scores |  | 96.3 | % |  | 96.3 | %
Schedule of Percentage of Consumer Loans Assigned Based on Unit Volumes | The following table shows the percentage of Consumer Loans assigned to us as Dealer Loans and Purchased Loans for each of the last five quarters:
|  | Unit Volume |  | Dollar Volume (1)
Three Months Ended |  | Dealer Loans |  | Purchased Loans |  | Dealer Loans |  | Purchased Loans
March 31, 2017 |  | 73.3 | % |  | 26.7 | % |  | 67.8 | % |  | 32.2 | %
June 30, 2017 |  | 72.3 | % |  | 27.7 | % |  | 67.9 | % |  | 32.1 | %
September 30, 2017 |  | 71.9 | % |  | 28.1 | % |  | 68.6 | % |  | 31.4 | %
December 31, 2017 |  | 72.5 | % |  | 27.5 | % |  | 69.7 | % |  | 30.3 | %
March 31, 2018 |  | 70.1 | % |  | 29.9 | % |  | 67.4 | % |  | 32.6 | %
(1) | Represents advances paid to Dealers on Consumer Loans assigned under our Portfolio Program and one-time payments made to Dealers to purchase Consumer Loans assigned under our Purchase Program. Payments of Dealer Holdback and accelerated Dealer Holdback are not included.

X
- Definition Description Of Business [Abstract] + References No definition available. + Details
Name: | cacc_DescriptionOfBusinessAbstract
Namespace Prefix: | cacc_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Schedule Of Percentage Of Consumer Loans Assigned Based On Unit Volumes Table Text Block + References No definition available. + Details
Name: | cacc_ScheduleOfPercentageOfConsumerLoansAssignedBasedOnUnitVolumesTableTextBlock
Namespace Prefix: | cacc_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of financing receivables by credit quality indicator. The credit quality indicator is a statistic about the credit quality of financing receivables. Examples include, but not limited to, consumer credit risk scores, credit-rating-agency ratings, an entity's internal credit risk grades, loan-to-value ratios, collateral, collection experience and other internal metrics. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 55 -Paragraph 19 -URI http://asc.fasb.org/extlink&oid=82894031&loc=SL6953803-111525 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 29 -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953659-111524 + Details
Name: | us-gaap_FinancingReceivableCreditQualityIndicatorsTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration