Note 7 - Floor Plan Notes Payable and Lines of Credit (Details Textual) - USD ($)	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014
GE Capital Credit Agreement [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument, Basis Spread on Variable Rate	2.03%
GE Capital Credit Agreement [Member] \| If Terminated After July 11, 2015 [Member]
Debt Instrument, Prepayment Processing Fee Amount	$ 300,000
GE Capital Credit Agreement [Member]
Line of Credit Facility, Maximum Borrowing Capacity	$ 850,000,000
Debt Instrument, Interest Rate, Effective Percentage	2.64%
Debt Instrument, Working Capital Fee Percentage	0.35%
Floor Plan Notes Payable	$ 628,200,000
Ford Motor Financing Agreement [Member] \| Prime Rate [Member]
Debt Instrument, Basis Spread on Variable Rate	1.50%
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Minimum	3.75%
Ford Motor Financing Agreement [Member]
Debt Instrument, Interest Rate, Effective Percentage	5.25%
Floor Plan Notes Payable	$ 62,400,000
Long-term Line of Credit	0
Line of Credit Facility, Maximum Borrowing Capacity	17,500,000
Floor Plan Notes Payable	$ 854,758,000	$ 845,977,000
Debt, Weighted Average Interest Rate	1.47%	1.16%
Line of Credit Amount Pledged to Secure Letters of Credit	$ 12,700,000
Line of Credit Facility, Remaining Borrowing Capacity	$ 4,800,000

Amount of prepayment processing fee payable to lenders.

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- Definition

Working capital fee percentage.

+ References

No definition available.

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- Definition

Amounts borrowed to finance the purchase of new and used commercial vehicle inventory.

+ References

No definition available.

+ Details

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- Definition

Line of credit, amount pledged to secure letters of credit.

+ References

No definition available.

+ Details

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

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- Definition

Minimum contractual interest rate for funds borrowed, under the debt agreement.

+ References

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- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.16)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.16)
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 19, 20, 22
-Article 5

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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