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Commitments and Contingencies (Details Textual) $ in Millions | 12 Months Ended
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Dec. 31, 2017 USD ($) dealerships
Manufacturer [Line Items] |
Payments for Legal Settlements | $ 1,210
Volkswagen legal claims | $ 14,700
Number of Volkswagen dealers | 652
Proceeds from Legal Settlements | $ 0
Volkswagen [Member] |
Manufacturer [Line Items] |
New vehicle retail unit sales | 2.60%
Number Of Dealerships | dealerships | 7
TotalNumberOfInstallments | 18
NumberOfInstallmentsReceived | 11,000

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- Definition The amount of cash paid for the settlement of litigation or for other legal issues during the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 25 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3536-108585 + Details
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