Restructuring, Impairment and Other Charges - Summary of Restructuring Accrual Activity (Detail) (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013
Restructuring Cost and Reserve [Line Items]
Beginning balance	$ 2,807	$ 3,794
Restructuring charges recorded	1,200	1,100
Ending balance	2,723	3,195
Employee Severance [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges recorded	930	872
Cash payments related to liabilities recorded on exit or disposal activities	(1,029)	(1,399)
Net employee severance activity	(99)	(527)
Vacated Facility/Lease Termination [Member]
Restructuring Cost and Reserve [Line Items]
Revision of estimated liabilities	138	212
Cash payments related to liabilities recorded on exit or disposal activities	(123)	(284)
Net employee severance activity	$ 15	$ (72)