Goodwill and Intangible Assets - Intangible Assets (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 57,771	$ 57,455
Accumulated Amortization	9,675	6,245
Net Carrying Amount	48,096	51,210
Trademarks and patents
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	1,030	879
Accumulated Amortization	199	140
Net Carrying Amount	831	739
Technology
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	35,752	35,769
Accumulated Amortization	7,355	4,655
Net Carrying Amount	28,397	31,114
Covenant not-to-compete
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	998	956
Accumulated Amortization	293	135
Net Carrying Amount	705	821
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	19,991	19,851
Accumulated Amortization	1,828	1,315
Net Carrying Amount	$ 18,163	$ 18,536