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Financial Instruments and Fair Value Measurements - Impact of Interest Rate Derivative Instruments (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2020 | Mar. 31, 2019 | Dec. 31, 2019
Derivative [Line Items] |  |  |
Amount of unrealized income (loss), net of tax, recognized in other comprehensive (loss) income | $ (31.6) | $ (4.2) | $ (4.2)
Amount of income (loss) reclassified from other comprehensive (loss) income into statements of operations | (0.5) | $ 0.3 |
Floorplan interest expense, net |  |  |
Derivative [Line Items] |  |  |
Amount of income (loss) reclassified from other comprehensive (loss) income into statements of operations | (0.6) |  | 0.3
Other interest expense, net |  |  |
Derivative [Line Items] |  |  |
Amount of income (loss) reclassified from other comprehensive (loss) income into statements of operations | $ (0.1) |  | $ 0.1

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- Definition Amount, after tax and before reclassification, of gain (loss) from derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=118930883&loc=SL7669646-108580 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=118930883&loc=d3e637-108580 + Details
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