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FINANCIAL INSTRUMENTS AND FAIR VALUE MEASUREMENTS - Impact of Interest Rate Derivative Instruments (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2021 | Jun. 30, 2020 | Jun. 30, 2021 | Jun. 30, 2020
Derivative |  |  |  |
Amount of unrealized income (loss), net of tax, recognized in other comprehensive (loss) income | $ (11.1) | $ (7.0) | $ 16.7 | $ (38.6)
Amount of income (loss) reclassified from other comprehensive (loss) income into statements of operations | (1.9) | (2.1) | (4.2) | (2.7)
Floorplan interest expense |  |  |  |
Derivative |  |  |  |
Amount of income (loss) reclassified from other comprehensive (loss) income into statements of operations | (1.4) | (2.1) | (3.7) | (2.7)
Other interest expense, net |  |  |  |
Derivative |  |  |  |
Amount of income (loss) reclassified from other comprehensive (loss) income into statements of operations | $ (1.0) | $ (0.7) | $ (1.9) | $ (0.8)

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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=124509347&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=124509347&loc=d3e637-108580 + Details
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- Definition Amount, after tax, of reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for 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 15 -URI http://asc.fasb.org/extlink&oid=124509347&loc=d3e689-108580 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=124509347&loc=d3e637-108580 + Details
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