Summary of Contingent Consideration by Acquisition (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended	3 Months Ended	6 Months Ended		3 Months Ended	6 Months Ended
	Jun. 30, 2012	Jun. 30, 2012	Jun. 30, 2012 idOnDemand, Inc.	Jun. 30, 2012 idOnDemand, Inc.	Jun. 30, 2013 idOnDemand, Inc.	Jun. 30, 2012 polyright SA	Jun. 30, 2012 polyright SA	Dec. 31, 2012 polyright SA
Business Acquisition Contingent Consideration [Line Items]
Maximum amount payable	$ 21,737	$ 21,737	$ 21,000	$ 21,000		$ 737	$ 737
Amount paid
Expense (income) recognized for changes in fair value	(6,086)	(5,657)	(5,875)	(5,463)		(211)	(194)
Amount outstanding	$ 108	$ 108			$ 10,000	$ 108	$ 108	$ 300