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Interim Financial Information (Details Textual) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2016 dealerships town states | Dec. 31, 2015 USD ($)
Business And Organization [Line Items] |  |
Number of Domestic Regions | 2 |
Number of International Regions | 2 |
Number of Reportable Segments | 3 |
Variable Interest Entity, Ownership Percentage | 8.00% |
Deferred income taxes | $ |  | $ 14.1
Debt Issuance Costs, Current Assets | $ |  | 0.5
Debt Issuance Costs, Long-term Assets | $ |  | $ 3.6
East [Member] |  |
Business And Organization [Line Items] |  |
Number of Dealerships | 36 |
West [Member] |  |
Business And Organization [Line Items] |  |
Number of Dealerships | 76 |
U.S. [Member] |  |
Business And Organization [Line Items] |  |
Number of States in which Entity Operates | states | 14 |
U.K. [Member] |  |
Business And Organization [Line Items] |  |
Number of Towns in which Entity Operates | town | 19 |
Number of Dealerships | 29 |
Brazil [Member] |  |
Business And Organization [Line Items] |  |
Number of States in which Entity Operates | states | 4 |
Number of Dealerships | 18 |

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