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v3.20.4

Acquisitions and Dispositions (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2020 USD ($) franchise dealership | Dec. 31, 2019 USD ($) dealership franchise | Dec. 31, 2018 USD ($) dealership franchise
Business Acquisition [Line Items] |  |  |
Aggregate consideration paid for dealerships | $ | $ 1.3 | $ 143.2 | $ 140.4
Cash received in acquisition | $ |  |  | 5.1
Net pre-tax gain (loss) on dealership dispositions | $ | $ (3.1) | $ 5.0 | $ 24.4
U.S. |  |  |
Business Acquisition [Line Items] |  |  |
Number of dealerships acquired |  | 4 | 4
Number of franchises acquired | franchise |  | 6 | 4
Number of dealerships opened |  | 1 | 1
Number of franchises awarded | franchise |  | 1 | 1
Number of dealerships disposed | 2 | 4 | 2
Number of franchises disposed | franchise | 3 | 7 | 3
Number of franchises terminated |  | 2 | 1
Net pre-tax gain (loss) on dealership dispositions | $ | $ 3.1 |  | $ 25.2
U.K. |  |  |
Business Acquisition [Line Items] |  |  |
Number of dealerships acquired |  | 4 | 5
Number of franchises acquired | franchise |  | 5 | 8
Number of dealerships opened |  | 2 | 1
Number of franchises awarded | franchise |  | 3 | 1
Number of franchises added | franchise |  |  | 1
Number of dealerships disposed |  | 3 | 1
Number of franchises disposed |  |  | 1
Number of franchises terminated |  | 4 | 1
Net pre-tax gain (loss) on dealership dispositions | $ | $ 2.2 |  |
Brazil |  |  |
Business Acquisition [Line Items] |  |  |
Number of dealerships acquired |  |  | 1
Number of franchises acquired | franchise |  |  | 1
Number of dealerships opened |  |  | 1
Number of franchises awarded | franchise |  |  | 1
Number of dealerships disposed |  | 1 |
Number of franchises disposed | franchise |  | 1 |

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