Goodwill and Intangible Assets (Detail) - Intangible assets (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Dec. 31, 2012
Intangible Assets, Gross	$ 7,637	$ 7,745
Less accumulated amortization	(3,499)	(3,376)
Intangible Assets, Net	4,138	4,369
Trade Names [Member]
Finite-Lived Intangible Asset Useful Life	15 - 20
Intangible Assets, Gross	1,388	1,404
Patents [Member]
Finite-Lived Intangible Asset Useful Life	5 - 12
Intangible Assets, Gross	4,994	5,072
Customer Relationships [Member]
Finite-Lived Intangible Asset Useful Life	4 - 8
Intangible Assets, Gross	$ 1,255	$ 1,269

Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16212-109274

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph ((a)(1),(b))

-URI http://asc.fasb.org/extlink&oid=7658586&loc=d3e16323-109275

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 142

-Paragraph 42, 45

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Name:	us-gaap_IntangibleAssetsNetExcludingGoodwill
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant