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Business Combinations (Details) - item | 9 Months Ended
--- | ---
Sep. 30, 2015 | Sep. 30, 2014
Retail Automotive Franchise |  |
Business combinations |  |
Number of acquired franchises | 1 | 2
Retail Commercial Truck Dealership |  |
Business combinations |  |
Number of acquired franchises | 2 |

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- Definition Number of franchises acquired. + References No definition available. + Details
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Balance Type: | na
Period Type: | duration

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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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- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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- Details
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Namespace Prefix: |
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Balance Type: |
Period Type: |