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Inventories, Net - Summary of Inventories (Details) - USD ($) $ in Millions | Dec. 31, 2019 | Dec. 31, 2018
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Inventory Disclosure [Abstract] |  |
New vehicles | $ 1,328.6 | $ 1,274.3
Used vehicles | 346.7 | 347.4
Rental vehicles | 140.9 | 142.9
Parts, accessories and other | 85.5 | 79.4
Total inventories, net | $ 1,901.7 | $ 1,844.1

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- Definition Gross amount, as of the balance sheet date, of merchandise, goods, commodities, or supplies held for future sale or to be used in manufacturing, servicing or production process. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.6(a)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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