Components of Other Intangible Assets (Detail) (USD $) In Thousands, unless otherwise specified				12 Months Ended						12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2012 Non-compete agreements	Dec. 31, 2011 Non-compete agreements	Dec. 31, 2012 Dealer/customer related	Dec. 31, 2011 Dealer/customer related	Dec. 31, 2011 Developed technology	Dec. 31, 2012 Developed technology	Dec. 31, 2012 Developed technology Minimum	Dec. 31, 2012 Developed technology Maximum	Dec. 31, 2012 Brand/Trade Names	Dec. 31, 2011 Brand/Trade Names
Intangible Assets by Major Class [Line Items]
Total Estimated Life (years)				5 years	5 years	7 years	7 years	7 years		5 years	7 years
Amortizable, Gross Carrying Amount	$ 28,216	$ 16,878		$ 540	$ 240	$ 14,702	$ 8,013	$ 8,625	$ 12,974
Accumulated Amortization	(4,015)	(1,206)	(188)	(77)	(24)	(1,650)	(366)	(816)	(2,288)
Non-amortizable, Gross Carrying Amount												26,691	17,378
Amortizable, Net	24,201	15,672		463	216	13,052	7,647	7,809	10,686
Total other intangible assets, Gross Carrying Amount	54,907	34,256	3,147
Non-amortizable, Net												26,691	17,378
Total other intangible assets, net	$ 50,892	$ 33,050