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Inventory And Vehicle Floorplan Payable (Components Of Inventory) (Details) - USD ($) $ in Millions | Mar. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Inventory [Line Items] |  |
Inventory | $ 2,254.6 | $ 2,598.5
New Vehicle [Member] |  |
Inventory [Line Items] |  |
Inventory | 1,363.6 | 1,761.9
Used Vehicle [Member] |  |
Inventory [Line Items] |  |
Inventory | 698.8 | 648.4
Parts and Service [Member] |  |
Inventory [Line Items] |  |
Inventory | $ 192.2 | $ 188.2

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- Definition Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section 45 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121566466&loc=d3e6676-107765 Reference 2: 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=120391452&loc=d3e13212-122682 + Details
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- Details
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- Details
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