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Intangibles - Narrative (Details) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2019 USD ($) dealership | Sep. 30, 2019 USD ($)
Finite-Lived Intangible Assets [Line Items] |  |
Additional indefinite-lived intangibles assets | $ 3.1 |
Additional goodwill acquired |  | $ 20.6
U.K. |  |
Finite-Lived Intangible Assets [Line Items] |  |
Number of dealerships below carrying values | dealership | 7 |
Franchise asset impairment charges | $ 5.6 |
Additional goodwill acquired | $ 1.3 | 1.3
U.S. |  |
Finite-Lived Intangible Assets [Line Items] |  |
Number of dealerships below carrying values | dealership | 1 |
Franchise asset impairment charges | $ 3.0 |
Additional goodwill acquired | $ 19.3 | $ 19.3

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