Note 6 - Valuation Accounts (Details) - Valuation and Allowance Accounts (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Allowance for Trade Receivables [Member]
2014
Balance	$ 821	$ 540	$ 480
Net Charged to Costs and Expenses	919	1,163	922
Net Write - Offs	(1,101)	(882)	(862)
Balance	639	821	540
Allowance for Warranty Receivables from Manufacturers [Member]
2014
Balance	419	444	480
Net Charged to Costs and Expenses	411	626	334
Net Write - Offs	(690)	(651)	(370)
Balance	140	419	444
Parts Inventory [Member]
2014
Balance	4,416	3,593	3,406
Net Charged to Costs and Expenses	2,547	2,560	1,796
Net Write - Offs	(1,896)	(1,737)	(1,609)
Balance	5,067	4,416	3,593
Commercial Vehicle Inventory [Member]
2014
Balance	7,395	6,839	1,624
Net Charged to Costs and Expenses	17,416	13,020	12,944
Net Write - Offs	(14,167)	(12,464)	(7,729)
Balance	$ 10,644	$ 7,395	$ 6,839

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Total of allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 09

-Article 12

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- Definition

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- Definition

Total of the deductions in a given period to allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs, representing receivables written off as uncollectible and portions of the reserves utilized, respectively.

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