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FINANCIAL INSTRUMENTS AND FAIR VALUE MEASUREMENTS - Impact of Interest Rate Derivative Instruments (Details) - USD ($) $ in Millions | 3 Months Ended
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Mar. 31, 2024 | Mar. 31, 2023
Derivative |  |
Amount of Unrealized Income (Loss), Net of Tax, Recognized in Other Comprehensive Income (Loss) | $ 14.3 | $ (6.7)
Amount Reclassified from Other Comprehensive Income (Loss) into Statements of Operations | 7.5 | 5.7
Floorplan interest expense |  |
Derivative |  |
Amount Reclassified from Other Comprehensive Income (Loss) into Statements of Operations | 5.3 | 3.3
Other interest expense, net |  |
Derivative |  |
Amount Reclassified from Other Comprehensive Income (Loss) into Statements of Operations | $ 4.6 | $ 4.2

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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 -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 11 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482790/220-10-45-11 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 10A -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482790/220-10-45-10A + 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 -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 11 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482790/220-10-45-11 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 15 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482790/220-10-45-15 + Details
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