XML 77 R72.htm IDEA: XBRL DOCUMENT
v3.19.3.a.u2

Debt (Narrative) (Details) |  |  |  |  | 12 Months Ended |
--- | --- | --- | --- | --- | --- | ---
Jan. 17, 2020 USD ($) | Mar. 30, 2015 USD ($) | Feb. 21, 2014 USD ($) | Jan. 22, 2014 USD ($) | Dec. 31, 2019 USD ($) facility | Dec. 31, 2018 USD ($) | Dec. 31, 2017 USD ($) | Sep. 30, 2016
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Senior notes |  |  |  |  |  | $ 1,187,800,000 |  | $ 544,400,000 |  |
Document Period End Date |  |  |  |  |  | Dec. 31, 2019 |  |  |  |
Maximum hedging reserve |  |  |  |  |  | $ 1,000,000.0 |  |  |  |
Percentage of collections on contributed loans |  |  |  |  |  | 6.00% |  |  |  |
Monthly servicing fee per financing |  |  |  |  |  | 6.00% |  |  |  |
Repayments of senior notes |  |  |  |  |  | $ 148,200,000 |  | 0 | $ 0 |
Loss on extinguishment of debt |  |  |  |  |  | 1,800,000 |  | 0 | 0 |
Debt covenants |  |  |  |  |  | 1 |  |  |  |
Proceeds from issuance of senior notes |  |  |  |  |  | $ 800,000,000.0 |  | 0 | $ 0 |
Revolving Secured Line Of Credit [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Debt maturity date |  |  |  |  |  | Jun. 22, 2022 |  |  |  |
Line of credit facility |  |  |  |  |  | $ 340,000,000.0 |  |  |  |
Percentage of net book value of loans |  |  |  |  |  | 80.00% |  |  |  |
Warehouse Facilities [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Percentage of net book value of loans |  |  |  |  |  | 80.00% |  |  |  |
Number of warehouse facilities | facility |  |  |  |  |  | 6 |  |  |  |
Debt financing amount |  |  |  |  |  | $ 1,225,000,000.0 |  |  |  |
Warehouse Facility II [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Debt maturity date | [1] |  |  |  |  | Jul. 12, 2022 |  |  |  |
Debt financing amount |  |  |  |  |  | $ 400,000,000.0 | [2] | $ 400,000,000.0 |  |
Interest rate |  |  |  |  |  | 0.00% |  | 0.00% |  |
Warehouse Facility IV [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Debt maturity date | [1] |  |  |  |  | Jul. 26, 2022 |  |  |  |
Debt financing amount |  |  |  |  |  | $ 300,000,000.0 | [2] | $ 250,000,000.0 |  |
Interest rate |  |  |  |  |  | 0.00% |  | 0.00% |  |
Warehouse Facility V [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Debt maturity date | [3] |  |  |  |  | Aug. 17, 2021 |  |  |  |
Debt financing amount |  |  |  |  |  | $ 100,000,000.0 | [2] | $ 100,000,000.0 |  |
Interest rate |  |  |  |  |  | 0.00% |  | 0.00% |  |
Warehouse Facility VI [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Debt maturity date | [1] |  |  |  |  | Sep. 30, 2022 |  |  |  |
Debt financing amount |  |  |  |  |  | $ 75,000,000.0 |  |  |  |
Interest rate |  |  |  |  |  | 0.00% |  | 0.00% |  |
2017 Senior Notes [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Senior notes stated interest rate |  |  |  |  |  |  |  |  |  | 9.125%
Debt Instrument, Repurchase Date |  |  |  | Feb. 21, 2014 |  |  |  |  |  |
Repayments of senior notes |  |  |  | $ 350,000,000.0 |  |  |  |  |  |
Loss on extinguishment of debt |  |  |  | $ (21,800,000) |  |  |  |  |  |
2021 Senior Notes [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Senior notes |  |  |  |  |  | $ 151,800,000 |  | $ 300,000,000.0 |  |
Debt Instrument, Issuance Date |  |  |  |  | Jan. 22, 2014 |  |  |  |  |
Debt maturity date |  |  |  |  | Feb. 15, 2021 | Feb. 15, 2021 | [4] |  |  |
Debt financing amount |  |  |  |  | $ 300,000,000.0 | $ 151,800,000 |  |  |  |
Senior notes stated interest rate |  |  |  |  | 6.125% |  |  |  |  |
Interest rate |  |  |  |  |  | 6.125% |  | 6.125% |  |
2023 Senior Notes [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Senior notes |  |  |  |  |  | $ 250,000,000.0 |  | $ 250,000,000.0 |  |
Debt Instrument, Issuance Date |  |  | Mar. 30, 2015 |  |  |  |  |  |  |
Debt maturity date |  |  | Mar. 15, 2023 |  |  | Mar. 15, 2023 | [4] |  |  |
Debt financing amount |  |  | $ 250,000,000.0 |  |  | $ 250,000,000.0 |  |  |  |
Senior notes stated interest rate |  |  | 7.375% |  |  |  |  |  |  |
Redemption price, percentage of principal amount redeemed |  |  | 99.266% |  |  |  |  |  |  |
Proceeds from issuance of senior notes |  |  | $ 248,200,000 |  |  |  |  |  |  |
Interest rate |  |  | 7.50% |  |  | 7.375% |  | 7.375% |  |
2024 Senior Notes [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Senior notes |  |  |  |  |  | $ 400,000,000.0 |  | $ 0 |  |
Debt maturity date |  |  |  |  |  | Dec. 31, 2024 |  |  |  |
Debt financing amount |  |  |  |  |  | $ 400,000,000.0 |  |  |  |
Interest rate |  |  |  |  |  | 5.125% |  | 0.00% |  |
2026 Senior Notes [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Senior notes |  |  |  |  |  | $ 400,000,000.0 |  | $ 0 |  |
Debt maturity date |  |  |  |  |  | Mar. 15, 2026 |  |  |  |
Debt financing amount |  |  |  |  |  | $ 400,000,000.0 |  |  |  |
Interest rate |  |  |  |  |  | 6.625% |  | 0.00% |  |
Mortgage [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Senior notes |  |  |  |  |  | $ 11,300,000 |  | $ 11,900,000 |  |
Debt maturity date |  |  |  |  |  | Aug. 06, 2023 |  |  |  |
Debt financing amount |  |  |  |  |  | $ 12,000,000.0 |  |  |  |
Interest rate |  |  |  |  |  | 3.21% |  | 3.85% |  |
London Interbank Offered Rate (LIBOR) [Member] | Revolving Secured Line Of Credit [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Debt Instrument, Basis Spread on Variable Rate |  |  |  |  |  | 18750.00% |  |  |  |
London Interbank Offered Rate (LIBOR) [Member] | Warehouse Facility II [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Debt Instrument, Basis Spread on Variable Rate |  |  |  |  |  | 17500.00% |  |  |  |
London Interbank Offered Rate (LIBOR) [Member] | Warehouse Facility IV [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Debt Instrument, Basis Spread on Variable Rate |  |  |  |  |  | 20000.00% |  |  |  |
London Interbank Offered Rate (LIBOR) [Member] | Warehouse Facility V [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Debt Instrument, Basis Spread on Variable Rate |  |  |  |  |  | 19000.00% |  |  |  |
London Interbank Offered Rate (LIBOR) [Member] | Warehouse Facility VI [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Debt Instrument, Basis Spread on Variable Rate |  |  |  |  |  | 20000.00% |  |  |  |
London Interbank Offered Rate (LIBOR) [Member] | Mortgage [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Debt Instrument, Basis Spread on Variable Rate |  |  |  |  |  | 15000.00% |  |  |  |
Prime Rate [Member] | Revolving Secured Line Of Credit [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Debt Instrument, Basis Spread on Variable Rate |  |  |  |  |  | 8750.00% |  |  |  |
Subsequent Event [Member] | 2021 Senior Notes [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Repayments of senior notes |  | $ 151,800,000 |  |  |  |  |  |  |  |
[1] | Represents the revolving maturity date. The outstanding balance will amortize after the revolving maturity date based on the cash flows of the pledged assets.
[2] | Interest rate cap agreements are in place to limit the exposure to increasing interest rates.
[3] | Represents the revolving maturity date. The outstanding balance will amortize after the revolving maturity date and any amounts remaining on August 17, 2023 will be due on that date.
[4] | On January 17, 2020, we used a portion of the net proceeds from the 2024 senior notes to redeem the remaining $151.8 million outstanding principal amount of the 2021 senior notes. We intend to use the remaining net proceeds from the 2024 senior notes, together with borrowings under our revolving credit facility and cash on hand to the extent available, to redeem in full the $250.0 million outstanding principal amount of the 2023 senior notes on or around March 15, 2020.

X
- Definition Debt Instrument Covenant Net Income For Past Two Quarters + References No definition available. + Details
Name: | cacc_DebtInstrumentCovenantNetIncomeForPastTwoQuarters
Namespace Prefix: | cacc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Maximum hedging reserve + References No definition available. + Details
Name: | cacc_MaximumHedgingReserve
Namespace Prefix: | cacc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Monthly Servicing Fee Per Financing + References No definition available. + Details
Name: | cacc_MonthlyServicingFeePerFinancing
Namespace Prefix: | cacc_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number Warehouse Facilities + References No definition available. + Details
Name: | cacc_NumberWarehouseFacilities
Namespace Prefix: | cacc_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of collections on contributed loans + References No definition available. + Details
Name: | cacc_PercentageOfCollectionsOnContributedLoans
Namespace Prefix: | cacc_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of net book value of loans, maximum. + References No definition available. + Details
Name: | cacc_PercentageOfNetBookValueOfLoans
Namespace Prefix: | cacc_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition The end date of the period reflected on the cover page if a periodic report. For all other reports and registration statements containing historical data, it is the date up through which that historical data is presented. If there is no historical data in the report, use the filing date. The format of the date is CCYY-MM-DD. + References No definition available. + Details
Name: | dei_DocumentPeriodEndDate
Namespace Prefix: | dei_
Data Type: | xbrli:dateItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage points added to the reference rate to compute the variable rate on the debt instrument. + References No definition available. + Details
Name: | us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Face (par) amount of debt instrument at time of issuance. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400 + Details
Name: | us-gaap_DebtInstrumentFaceAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6036836-161870 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_DebtInstrumentInterestRateEffectivePercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Date the debt instrument was issued, in CCYY-MM-DD format. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_DebtInstrumentIssuanceDate1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:dateItemType
Balance Type: | na
Period Type: | duration

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_DebtInstrumentLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(2)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb)(2) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
Name: | us-gaap_DebtInstrumentMaturityDate
Namespace Prefix: | us-gaap_
Data Type: | xbrli:dateItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of principal amount of debt redeemed. + References No definition available. + Details
Name: | us-gaap_DebtInstrumentRedemptionPricePercentageOfPrincipalAmountRedeemed
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Date the debt instrument was repurchased, in CCYY-MM-DD format. + References No definition available. + Details
Name: | us-gaap_DebtInstrumentRepurchaseDate
Namespace Prefix: | us-gaap_
Data Type: | xbrli:dateItemType
Balance Type: | na
Period Type: | duration

X
- Definition Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 50 -Section 40 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=117329964&loc=d3e12355-112629 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 50 -Section 40 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=117329964&loc=d3e12317-112629 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585 + Details
Name: | us-gaap_GainsLossesOnExtinguishmentOfDebt
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The cash inflow from a borrowing with the highest claim on the assets of the entity in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle, if longer). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3255-108585 + Details
Name: | us-gaap_ProceedsFromIssuanceOfSeniorLongTermDebt
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The cash outflow for a long-term debt where the holder has highest claim on the entity's asset in case of bankruptcy or liquidation during the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3291-108585 + Details
Name: | us-gaap_RepaymentsOfSeniorDebt
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion. Senior note holders are paid off in full before any payments are made to junior note holders. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_SeniorLongTermNotes
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | us-gaap_DebtInstrumentAxis=us-gaap_LineOfCreditMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=cacc_WarehouseFacilitiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=cacc_WarehouseFacilityIIMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=cacc_WarehouseFacilityIVMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=cacc_WarehouseFacilityVMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=cacc_WarehouseFacilityVIMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=cacc_TwoThousandSeventeenSeniorNotesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=cacc_TwoThousandTwentyOneSeniorNotesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=cacc_TwoThousandTwentyThreeSeniorNotesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=cacc_TwoThousandTwentyFourSeniorNotesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=cacc_TwoThousandTwentySixSeniorNotesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=us-gaap_MortgagesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_VariableRateAxis=us-gaap_LondonInterbankOfferedRateLIBORMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_VariableRateAxis=us-gaap_PrimeRateMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |