Goodwill and Other Intangibles - Components of Identifiable Intangible Assets (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	$ 10,503	$ 8,695
Accumulated Amortization	4,376	3,504
Net Carrying Value	6,127	5,191
Patents [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	5,653	5,108
Accumulated Amortization	1,768	1,339
Net Carrying Value	3,885	3,769
Trademarks and Technology Licenses [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	1,417	1,157
Accumulated Amortization	900	821
Net Carrying Value	517	336
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	2,593	1,757
Accumulated Amortization	1,294	1,001
Net Carrying Value	1,299	756
Other Intangible Assets [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	840	673
Accumulated Amortization	414	343
Net Carrying Value	$ 426	$ 330