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v3.19.2

Debt (Schedule of General Information of Financing Transaction) (Details) - USD ($) |  |  |  |  | 6 Months Ended |
--- | --- | --- | --- | --- | --- | ---
Mar. 07, 2019 | Aug. 06, 2018 | Mar. 30, 2015 | Jan. 22, 2014 | Jun. 30, 2019 | Dec. 31, 2018
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Document Period End Date |  |  |  |  |  | Jun. 30, 2019 |  |
Senior notes |  |  |  |  |  | $ 939,600,000 |  | $ 544,400,000
Revolving Secured Line of Credit [Member] |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Wholly-owned Subsidiary |  |  |  |  |  | n/a |  |
Line of credit maturity date |  |  |  |  |  | Jun. 22, 2022 |  |
Financing Amount |  |  |  |  |  | $ 340,000,000.0 |  |
Revolving Secured Line of Credit [Member] | LIBOR [Member] |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Basis spread on variable rate |  |  |  |  |  | 18750.00% |  |
Revolving Secured Line of Credit [Member] | Prime Rate [Member] |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Basis spread on variable rate |  |  |  |  |  | 8750.00% |  |
Warehouse Facility II [Member] |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Interest rate |  |  |  |  |  | 4.19% |  | 0.00%
Wholly-owned Subsidiary | [1] |  |  |  |  | CAC Warehouse Funding Corp. II |  |
Debt maturity date | [1],[2] |  |  |  |  | Dec. 20, 2020 |  |
Debt facility financing amount | [1],[3] |  |  |  |  | $ 400,000,000.0 |  |
Warehouse Facility II [Member] | LIBOR [Member] |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Basis spread on variable rate | [1],[3] |  |  |  |  | 17500.00% |  |
Warehouse Facility IV [Member] |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Interest rate |  |  |  |  |  | 0.00% |  | 0.00%
Wholly-owned Subsidiary | [1] |  |  |  |  | CAC Warehouse Funding LLC IV |  |
Debt maturity date | [1],[2] |  |  |  |  | Apr. 30, 2020 |  |
Debt facility financing amount |  |  |  |  |  | $ 250,000,000.0 | [1],[3] | $ 250,000,000.0
Warehouse Facility IV [Member] | LIBOR [Member] |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Basis spread on variable rate | [1],[3] |  |  |  |  | 22500.00% |  |
Warehouse Facility V [Member] |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Interest rate |  |  |  |  |  | 0.00% |  | 0.00%
Wholly-owned Subsidiary | [1] |  |  |  |  | CAC Warehouse Funding LLC V |  |
Debt maturity date | [1],[4] |  |  |  |  | Aug. 17, 2021 |  |
Debt facility financing amount | [1],[3] |  |  |  |  | $ 100,000,000.0 |  |
Warehouse Facility V [Member] | LIBOR [Member] |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Basis spread on variable rate | [1],[3] |  |  |  |  | 19000.00% |  |
Warehouse Facility VI [Member] |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Interest rate |  |  |  |  |  | 0.00% |  | 0.00%
Wholly-owned Subsidiary | [1] |  |  |  |  | CAC Warehouse Funding LLC VI |  |
Debt maturity date | [1],[2] |  |  |  |  | Sep. 30, 2020 |  |
Debt facility financing amount | [1],[3] |  |  |  |  | $ 75,000,000.0 |  |
Warehouse Facility VI [Member] | LIBOR [Member] |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Basis spread on variable rate | [1] |  |  |  |  | 20000.00% |  |
Warehouse Facility VII [Member] |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Interest rate |  |  |  |  |  | 4.65% |  | 0.00%
Wholly-owned Subsidiary | [1] |  |  |  |  | CAC Warehouse Funding LLC VII |  |
Debt maturity date | [1],[5] |  |  |  |  | Dec. 17, 2020 |  |
Debt facility financing amount | [1],[3] |  |  |  |  | $ 150,000,000.0 |  |
Warehouse Facility VII [Member] | Commercial Paper Offered Rate [Member] |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Basis spread on variable rate | [1],[3] |  |  |  |  | 20000.00% |  |
Term ABS 2016-1 [Member] |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Interest rate |  |  |  |  |  | 0.00% |  | 4.41%
Term ABS 2016-2 [Member] |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Interest rate |  |  |  |  |  | 4.06% |  | 3.20%
Wholly-owned Subsidiary | [1] |  |  |  |  | Credit Acceptance Funding LLC 2016-2 |  |
Debt maturity date | [1],[2] |  |  |  |  | May 15, 2018 |  |
Debt facility financing amount | [1] |  |  |  |  | $ 350,200,000 |  |
Term ABS 2016-3 [Member] |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Interest rate |  |  |  |  |  | 2.97% |  | 2.59%
Wholly-owned Subsidiary | [1] |  |  |  |  | Credit Acceptance Funding LLC 2016-3 |  |
Debt maturity date | [1],[2] |  |  |  |  | Oct. 15, 2018 |  |
Debt facility financing amount | [1] |  |  |  |  | $ 350,000,000.0 |  |
Term ABS 2017-1 [Member] |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Interest rate |  |  |  |  |  | 2.87% |  | 2.78%
Wholly-owned Subsidiary | [1] |  |  |  |  | Credit Acceptance Funding LLC 2017-1 |  |
Debt maturity date | [1],[2] |  |  |  |  | Feb. 15, 2019 |  |
Debt facility financing amount | [1] |  |  |  |  | $ 350,000,000.0 |  |
Term ABS 2017-2 [Member] |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Interest rate |  |  |  |  |  | 2.72% |  | 2.72%
Wholly-owned Subsidiary | [1] |  |  |  |  | Credit Acceptance Funding LLC 2017-2 |  |
Debt maturity date | [1],[2] |  |  |  |  | Jun. 17, 2019 |  |
Debt facility financing amount | [1] |  |  |  |  | $ 450,000,000.0 |  |
Term ABS 2017-3 [Member] |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Interest rate |  |  |  |  |  | 2.88% |  | 2.88%
Wholly-owned Subsidiary | [1] |  |  |  |  | Credit Acceptance Funding LLC 2017-3 |  |
Debt maturity date | [1],[2] |  |  |  |  | Oct. 15, 2019 |  |
Debt facility financing amount | [1] |  |  |  |  | $ 350,000,000.0 |  |
Term ABS 2018-1 [Member] |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Interest rate |  |  |  |  |  | 3.24% |  | 3.24%
Wholly-owned Subsidiary | [1] |  |  |  |  | Credit Acceptance Funding LLC 2018-1 |  |
Debt maturity date | [1],[2] |  |  |  |  | Feb. 17, 2020 |  |
Debt facility financing amount | [1] |  |  |  |  | $ 500,000,000.0 |  |
Term ABS 2018-2 [Member] |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Interest rate |  |  |  |  |  | 3.68% |  | 3.68%
Wholly-owned Subsidiary | [1] |  |  |  |  | Credit Acceptance Funding LLC 2018-2 |  |
Debt maturity date | [1],[2] |  |  |  |  | May 15, 2020 |  |
Debt facility financing amount | [1] |  |  |  |  | $ 450,000,000.0 |  |
Term ABS 2018-3 [Member] |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Interest rate |  |  |  |  |  | 3.72% |  | 3.72%
Wholly-owned Subsidiary | [1] |  |  |  |  | Credit Acceptance Funding LLC 2018-3 |  |
Debt maturity date | [1],[2] |  |  |  |  | Aug. 17, 2020 |  |
Debt facility financing amount | [1] |  |  |  |  | $ 398,300,000 |  |
Term ABS 2019-1 [Member] |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Interest rate |  |  |  |  |  | 3.53% |  |
Wholly-owned Subsidiary | [1] |  |  |  |  | Credit Acceptance Funding LLC 2019-1 |  |
Debt maturity date | [1],[2] |  |  |  |  | Feb. 15, 2021 |  |
Debt facility financing amount | [1] |  |  |  |  | $ 402,500,000 |  |
2021 Senior Notes [Member] |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Senior notes |  |  |  |  |  | $ 300,000,000.0 |  | $ 300,000,000.0
Interest rate |  |  |  |  |  | 6.125% |  | 6.125%
Wholly-owned Subsidiary |  |  |  |  |  | n/a |  |
Debt maturity date |  |  |  |  | Feb. 15, 2021 | Feb. 15, 2021 |  |
Debt facility financing amount |  |  |  |  | $ 300,000,000.0 | $ 300,000,000.0 |  |
2023 Senior Notes [Member] |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Senior notes |  |  |  |  |  | $ 250,000,000.0 |  | $ 250,000,000.0
Interest rate |  |  |  | 7.50% |  | 7.375% |  | 7.375%
Wholly-owned Subsidiary |  |  |  |  |  | n/a |  |
Debt maturity date |  | Mar. 15, 2026 |  | Mar. 15, 2023 |  | Mar. 15, 2023 |  |
Debt facility financing amount |  |  |  | $ 250,000,000.0 |  | $ 250,000,000.0 |  |
2026 Senior Notes [Member] |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Senior notes |  |  |  |  |  | $ 400,000,000.0 |  | $ 0
Interest rate |  |  |  |  |  | 6.625% |  | 0.00%
Wholly-owned Subsidiary |  |  |  |  |  | n/a |  |
Debt maturity date |  |  |  |  |  | Mar. 15, 2026 |  |
Debt facility financing amount |  | $ 400,000,000.0 |  |  |  | $ 400,000,000.0 |  |
Mortgages [Member] |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Interest rate |  |  |  |  |  | 3.94% |  | 3.85%
Wholly-owned Subsidiary |  |  |  |  |  | Chapter 4 Properties, LLC |  |
Debt maturity date |  |  | Aug. 06, 2023 |  |  | Aug. 06, 2023 |  |
Debt facility financing amount |  |  | $ 12,000,000.0 |  |  | $ 12,000,000.0 |  |
Mortgages [Member] | LIBOR [Member] |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Basis spread on variable rate | [1],[3] |  |  |  |  | 15000.00% |  |
[1] | Financing made available only to a specified subsidiary of the Company.
[2] | Represents the revolving maturity date. The outstanding balance will amortize after the revolving maturity date based on the cash flows of the pledged assets.
[3] | Interest rate cap agreements are in place to limit the exposure to increasing interest rates
[4] | 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.
[5] | Represents the revolving maturity date. The outstanding balance will amortize after the revolving maturity date and any amounts remaining on December 17, 2022 will be due on that date.

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- 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
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