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FINANCIAL INSTRUMENTS AND FAIR VALUE MEASUREMENTS - Impact of Interest Rate Derivative Instruments (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022
Derivative |  |  |  |
Amount of Unrealized Income (Loss), Net of Tax, Recognized in Other Comprehensive Income (Loss) | $ 15.1 | $ 31.9 | $ 27.3 | $ 84.8
Amount Reclassified from Other Comprehensive Income (Loss) into Statements of Operations | 6.7 | 1.4 | 18.6 | (1.6)
Floorplan interest expense |  |  |  |
Derivative |  |  |  |
Amount Reclassified from Other Comprehensive Income (Loss) into Statements of Operations | 4.1 | 0.7 | 11.2 | (1.4)
Other interest expense, net |  |  |  |
Derivative |  |  |  |
Amount Reclassified from Other Comprehensive Income (Loss) into Statements of Operations | $ 4.7 | $ 1.2 | $ 13.2 | $ (0.7)

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