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Financial Instruments And Fair Value Measurements (Nonfinancial Assets Measured on a Nonrecurring Basis) (Details) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2020 USD ($) store | Mar. 31, 2019 USD ($) | Dec. 31, 2019 USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Gain/(loss) on goodwill | $ (318.3) | $ 0.0 |
Goodwill impairment | $ 318.3 | 0.0 |
Franchise rights impairment, number of stores | store | 8 |  |
Franchise rights impairment | $ 57.5 | 0.0 |
Fair Value, Nonrecurring [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Gain/(loss) on goodwill | (318.3) | 0.0 |
Gain/(Loss) on franchise rights and other | (59.9) | 0.0 |
Gain/(Loss) on right-of-use assets | (0.4) | (0.2) |
Gain/(Loss) on assets held and used | (5.7) | 0.0 |
Goodwill impairment | 318.3 | 0.0 |
Impairment of intangible assets | 59.9 | 0.0 |
Impairment of long-lived assets held and used | 5.7 | 0.0 |
Impairment charges related to right-of-use assets | 0.4 | 0.2 |
Fair Value, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Goodwill | 457.5 | 0.0 |
Franchise rights and other | 26.2 | 0.0 |
Right-of-use assets | 1.4 | 0.1 |
Long-lived assets held and used | 1.8 | $ 0.0 |
Reported Value Measurement [Member] | Continuing Operations [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Assets held for sale | 36.7 |  | $ 40.6
Reported Value Measurement [Member] | Discontinued Operations [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Assets held for sale in discontinued operations | 8.0 |  | $ 8.0
Franchise Rights [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Franchise rights impairment | 57.5 |  |
Reporting Unit, Premium Luxury [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Gain/(loss) on goodwill | (257.4) |  |
Goodwill impairment | 257.4 |  |
Reporting Unit, Collision Centers [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Gain/(loss) on goodwill | (41.6) |  |
Goodwill impairment | 41.6 |  |
Reporting Unit, Parts Centers [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Gain/(loss) on goodwill | (19.3) |  |
Goodwill impairment | 19.3 |  |
Other Intangible Assets [Member] | Fair Value, Nonrecurring [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Gain/(Loss) on franchise rights and other | (2.4) |  |
Impairment of intangible assets | 2.4 |  |
Valuation Technique, Discounted Cash Flow [Member] | Franchise Rights [Member] | Fair Value, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Franchise rights and other | $ 24.6 |  |
Valuation Technique, Discounted Cash Flow [Member] | Franchise Rights [Member] | Fair Value, Nonrecurring [Member] | Measurement Input, Long-term Revenue Growth Rate [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Franchise rights, measurement input | 0.020 |  |
Valuation Technique, Discounted Cash Flow [Member] | Minimum [Member] | Franchise Rights [Member] | Fair Value, Nonrecurring [Member] | Measurement Input, Weighted Average Cost of Capital [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Franchise rights, measurement input | 0.077 |  |
Valuation Technique, Discounted Cash Flow [Member] | Minimum [Member] | Franchise Rights [Member] | Fair Value, Nonrecurring [Member] | Measurement Input, Discount Rate [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Franchise rights, measurement input | 0.111 |  |
Valuation Technique, Discounted Cash Flow [Member] | Minimum [Member] | Franchise Rights [Member] | Fair Value, Nonrecurring [Member] | Measurement Input, Long-term Pretax Income Margin [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Franchise rights, measurement input | 0.006 |  |
Valuation Technique, Discounted Cash Flow [Member] | Minimum [Member] | Franchise Rights [Member] | Fair Value, Nonrecurring [Member] | Measurement Input, Contributory Asset Charges [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Franchise rights, measurement input | 0.042 |  |
Valuation Technique, Discounted Cash Flow [Member] | Maximum [Member] | Franchise Rights [Member] | Fair Value, Nonrecurring [Member] | Measurement Input, Weighted Average Cost of Capital [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Franchise rights, measurement input | 0.086 |  |
Valuation Technique, Discounted Cash Flow [Member] | Maximum [Member] | Franchise Rights [Member] | Fair Value, Nonrecurring [Member] | Measurement Input, Discount Rate [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Franchise rights, measurement input | 0.143 |  |
Valuation Technique, Discounted Cash Flow [Member] | Maximum [Member] | Franchise Rights [Member] | Fair Value, Nonrecurring [Member] | Measurement Input, Long-term Pretax Income Margin [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Franchise rights, measurement input | 0.028 |  |
Valuation Technique, Discounted Cash Flow [Member] | Maximum [Member] | Franchise Rights [Member] | Fair Value, Nonrecurring [Member] | Measurement Input, Contributory Asset Charges [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Franchise rights, measurement input | 0.121 |  |
Valuation Technique, Discounted Cash Flow [Member] | Weighted Average [Member] | Franchise Rights [Member] | Fair Value, Nonrecurring [Member] | Measurement Input, Weighted Average Cost of Capital [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Franchise rights, measurement input | 0.084 |  |
Valuation Technique, Discounted Cash Flow [Member] | Weighted Average [Member] | Franchise Rights [Member] | Fair Value, Nonrecurring [Member] | Measurement Input, Discount Rate [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Franchise rights, measurement input | 0.121 |  |
Valuation Technique, Discounted Cash Flow [Member] | Weighted Average [Member] | Franchise Rights [Member] | Fair Value, Nonrecurring [Member] | Measurement Input, Long-term Pretax Income Margin [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Franchise rights, measurement input | 0.014 |  |
Valuation Technique, Discounted Cash Flow [Member] | Weighted Average [Member] | Franchise Rights [Member] | Fair Value, Nonrecurring [Member] | Measurement Input, Contributory Asset Charges [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Franchise rights, measurement input | 0.062 |  |

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