Commitments and Contingencies - Additional Information (Detail) (USD $)	1 Months Ended	3 Months Ended
	May 05, 2010	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012	Mar. 31, 2013 Santur Corporation	Dec. 31, 2012 Santur Corporation	Oct. 12, 2011 Santur Corporation
Commitments And Contingencies Disclosure [Line Items]
Rent expense		$ 600,000	$ 500,000
Agreement period not to refile claims	90 day
Total outstanding purchase obligations		26,200,000
Additional contingent payable amount							7,500,000
Fair value of contingent consideration		$ 959,000		$ 959,000	$ 959,000	$ 959,000