Note 6 - Valuation Accounts (Detail) - Valuation and Allowance Accounts (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Allowance for Trade Receivables [Member]
Balance Beginning of Year	$ 480	$ 1,040	$ 204
Net Charged to Costs and Expenses	922	627	1,645
Net Write - Offs	(862)	(1,187)	(809)
Balance End of Year	540	480	1,040
Allowance for Warranty Receivables from Manufacturers [Member]
Balance Beginning of Year	480	279	553
Net Charged to Costs and Expenses	334	336	794
Net Write - Offs	(370)	(135)	(1,068)
Balance End of Year	444	480	279
Parts Inventory [Member]
Balance Beginning of Year	3,406	2,055	1,956
Net Charged to Costs and Expenses	1,546	1,909	1,360
Acquisitions		650	43
Net Write - Offs	(1,609)	(1,208)	(1,304)
Balance End of Year	3,343	3,406	2,055
Commercial Vehicle Inventory [Member]
Balance Beginning of Year	1,624	1,275	2,909
Net Charged to Costs and Expenses	12,944	5,807	4,024
Net Write - Offs	(7,729)	(5,458)	(5,658)
Balance End of Year	6,839	1,624	1,275
Construction Equipment Inventory [Member]
Balance Beginning of Year			1,497
Net Charged to Costs and Expenses			$ (1,497)