Business Combinations (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Mar. 31, 2010	Jun. 30, 2011	Jun. 30, 2010
Business Acquisition [Line Items]
Number of franchises acquired		3	3
Business Acquisition Purchase Price Allocation Assets Acquired Liabilities Assumed And Consideration Paid
Accounts Receivable		$ 953	$ 0
Inventory		7,923	6,336
Other current assets		0	17
Property and equipment		1,671	0
Goodwill		7,038	3,014
Other assets		628	0
Current liabilities		(2,491)	(5)
Total Consideration		15,722	9,362
Seller financed/assumed debt		(1,711)	0
Cash used in dealership acquisitions		14,011	9,362
Business Combinations (Textuals) [Abstract]
Ownership percentage of joint venture exchanged	50.00%
Ownership percentage in franchises acquired by exchange of joint venture ownership	100.00%
Number of franchises acquired by exchange of joint venture ownership	3
Intangible Assets recorded in connection with exchange of joint venture ownership	13,331
Purchase price for acquired franchises		170,000
Mortgages entered into with respect to the newly acquired real estate		$ 28,240
Acquisition [Member]
Business Acquisition [Line Items]
Number of franchises acquired		4

Business acquisition purchase price allocation assets acquired liabilities assumed and consideration paid.

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Business combinations number of franchises acquired.

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Business combinations.

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Disposal group including discontinued operation intangible assets.

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Number of franchises acquired by exchange of joint venture ownership.

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Ownership percentage in franchises acquired by exchange of joint venture ownership.

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Ownership percentage of joint venture exchanged.

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Purchase price for acquired franchises.

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Amount of cash paid to acquire the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141R
-Paragraph 68
-Subparagraph f(1)

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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141
-Paragraph 51
-Subparagraph d

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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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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.

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

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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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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
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-Paragraph 52
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The amount of acquisition cost of a business combination allocated to liabilities assumed.

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-Paragraph 37
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-Publisher FASB
-Name Emerging Issues Task Force (EITF)
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The amount of acquisition cost of a business combination allocated to noncurrent assets of the acquired entity, except for property plant and equipment, intangible assets, and goodwill.

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-Publisher FASB
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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
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-Paragraph 37
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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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The balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the loan portfolio.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 60
-Paragraph 47

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 1
-Subparagraph c
-Article 7

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