Business Combinations (Details 2) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Summary of the aggregate consideration paid and the aggregate amounts of the assets acquired and liabilities assumed
Accounts receivable	$ 28,907	$ 953
Inventory	123,672	61,247
Other current assets	628
Property and equipment	64,150	40,190
Goodwill	61,713	107,498
Franchise Value	53,407	29,491
Other non-current assets	745	628
Current liabilities	(59,722)	(6,190)
Non-current liabilities	(23,330)
Total consideration	250,170	233,817
Seller financed/assumed debt		(1,711)
Cash used in dealership acquisitions	$ 250,170	$ 232,106

Amount of cash paid to acquire the entity.

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The total cost of the acquired entity including the cash paid to shareholders of acquired entities, fair value of debt and equity securities issued to shareholders of acquired entities, the fair value of the liabilities assumed, and direct costs of the acquisition.

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The amount of acquisition cost of a business combination allocated to inventory, including finished goods, work-in-process, and raw materials.

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The amount of acquisition cost of a business combination allocated to prepaid expenses and other current assets. Does not include amounts allocated to cash and cash equivalents, marketable securities, receivables, inventory, and assets not to be used.

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The amount of acquisition cost of a business combination allocated to receivables.

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

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Amount of goodwill arising from a business combination, which is the excess of the cost of the acquired entity over the amounts assigned to assets acquired and liabilities assumed.

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The amount of acquisition cost of a business combination allocated to an identifiable intangible asset that will not be amortized. Does not include goodwill.

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The amount of acquisition cost of a business combination allocated to noncurrent liabilities of the acquired entity.

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Amount of acquisition cost of a business combination allocated to other noncurrent assets not separately disclosed.

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The amount of acquisition cost of a business combination allocated to property, plant and equipment to be used in ongoing operations.

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