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INVENTORIES - Narrative (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Inventory Disclosure [Abstract] |  |  |
Lower of cost or net realizable value reserves | $ 4.1 | $ 8.7 |
Reduction in inventory cost for interest received from manufacturers | 1.3 | 7.4 |
Reduction in new vehicle cost of sales for interest assistance received related to vehicles sold | 54.2 | 47.3 | $ 49.1
Impairment of inventory | $ 0.1 | $ 0.9 | $ 16.1

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- Definition Manufacturer floorplan assistance recognized as reduction of cost of sales. + References No definition available. + Details
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