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Commitments and Contingencies - Additional Information (Details) - USD ($) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2020 | Dec. 31, 2019
Other Commitments [Line Items] |  |
Maximum exposure associated with general indemnifications | $ 43.3 | $ 46.5
General indemnifications minimum expiration period | 1 year |
General indemnifications maximum expiration period | 3 years |
Percentage of dealership that is accounted for under the equity method | 50.00% |
Contingent liability reserve balance after reduction | $ 4.3 |
Other accrued liabilities |  |
Other Commitments [Line Items] |  |
Amount reserved for pending proceedings | 0.4 | 1.2
Other long-term liabilities |  |
Other Commitments [Line Items] |  |
Amount reserved for pending proceedings | $ 0.2 | $ 0.3

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