Basis of Presentation	9 Months Ended
Sep. 30, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	BASIS OF PRESENTATION The accompanying unaudited consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“generally accepted accounting principles” or “GAAP”) for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements. In the opinion of management, all adjustments (consisting of normal recurring accruals) considered necessary for a fair presentation have been included. The results of operations for interim periods are not necessarily indicative of actual results achieved for full fiscal years. The consolidated balance sheet as of December 31, 2017 has been derived from the audited financial statements at that date but does not include all the information and footnotes required by GAAP for complete financial statements. For further information, refer to the consolidated financial statements and footnotes thereto included in the Annual Report on Form 10-K for the year ended December 31, 2017 for Credit Acceptance Corporation (the “Company”, “Credit Acceptance”, “we”, “our” or “us”). The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Actual results could differ from those estimates. We have evaluated events and transactions occurring subsequent to the consolidated balance sheet date of September 30, 2018 for items that could potentially be recognized or disclosed in these financial statements. We did not identify any items which would require disclosure in or adjustment to the consolidated financial statements. Reclassification Certain amounts for prior periods have been reclassified to conform to the current presentation. On January 1, 2018, we adopted Accounting Standards Update 2016-18, which was applied retrospectively and changed the presentation and classification of restricted cash and restricted cash equivalents in our consolidated statements of cash flows. For additional information, see Note 3 to the consolidated financial statements. Additionally, the fair value level of measurement of our revolving secured line of credit as of December 31, 2017 was reclassified from Level 1 to Level 2. For additional information, see Note 4 to the consolidated financial statements.

BASIS OF PRESENTATION

The accompanying unaudited consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“generally accepted accounting principles” or “GAAP”) for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements. In the opinion of management, all adjustments (consisting of normal recurring accruals) considered necessary for a fair presentation have been included. The results of operations for interim periods are not necessarily indicative of actual results achieved for full fiscal years. The consolidated balance sheet as of December 31, 2017 has been derived from the audited financial statements at that date but does not include all the information and footnotes required by GAAP for complete financial statements. For further information, refer to the consolidated financial statements and footnotes thereto included in the Annual Report on Form 10-K for the year ended December 31, 2017 for Credit Acceptance Corporation (the “Company”, “Credit Acceptance”, “we”, “our” or “us”).

The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Actual results could differ from those estimates.

We have evaluated events and transactions occurring subsequent to the consolidated balance sheet date of September 30, 2018 for items that could potentially be recognized or disclosed in these financial statements. We did not identify any items which would require disclosure in or adjustment to the consolidated financial statements.

Reclassification

Certain amounts for prior periods have been reclassified to conform to the current presentation. On January 1, 2018, we adopted Accounting Standards Update 2016-18, which was applied retrospectively and changed the presentation and classification of restricted cash and restricted cash equivalents in our consolidated statements of cash flows. For additional information, see Note 3 to the consolidated financial statements. Additionally, the fair value level of measurement of our revolving secured line of credit as of December 31, 2017 was reclassified from Level 1 to Level 2. For additional information, see Note 4 to the consolidated financial statements.