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Business Acquisitions and Dispositions - Additional Information (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2019 USD ($) store Franchise | Dec. 31, 2018 USD ($) store | Dec. 31, 2017 USD ($) store
Business Acquisition [Line Items] |  |  |
Number of franchise dealerships opened |  | 1 |
Number of stores opened |  |  | 1
Number of EchoPark opened | 1 | 3 |
Number of franchises disposed | 1 | 2 |
Number of franchises disposed mid-line | 9 | 5 |
Cash generated from disposition | $ | $ 250.7 | $ 128.7 | $ 38.2
Number of franchises terminated |  | 1 | 1
Number of terminated stores |  | 4 | 2
Number of dealerships held for sale | Franchise | 0 |  |
Pre-owned vehicle store |  |  |
Business Acquisition [Line Items] |  |  |
Business acquisition, consideration amount | $ |  | $ 76.6 |

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- Definition Number of EchoPark opened + References No definition available. + Details
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- Definition Number of Franchise Dealerships Opened + References No definition available. + Details
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- Definition Number of franchises disposed. + References No definition available. + Details
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- Definition Number of franchises disposed mid-line + References No definition available. + Details
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- Definition Number Of Franchises Terminated + References No definition available. + Details
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- Definition Number Of Stores Opened + References No definition available. + Details
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- Definition Number of Stores Terminated + References No definition available. + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 30 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=116859721&loc=d3e6613-128477 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 30 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=116859721&loc=d3e6578-128477 + Details
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- Details
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