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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, 2023 | Jun. 30, 2022 | Jun. 30, 2023 | Jun. 30, 2022
Derivative |  |  |  |
Amount of Unrealized Income (Loss), Net of Tax, Recognized in Other Comprehensive Income (Loss) | $ 15.8 | $ 19.0 | $ 9.0 | $ 53.0
Amount Reclassified from Other Comprehensive Income (Loss) into Statements of Operations | 3.2 | (1.2) | 8.8 | (3.0)
Floorplan interest expense |  |  |  |
Derivative |  |  |  |
Amount Reclassified from Other Comprehensive Income (Loss) into Statements of Operations | 3.8 | (0.9) | 7.1 | (2.1)
Other interest expense, net |  |  |  |
Derivative |  |  |  |
Amount Reclassified from Other Comprehensive Income (Loss) into Statements of Operations | $ 0.3 | $ (0.7) | $ 4.5 | $ (1.8)

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