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Schedule of Restructuring and Other Net (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2014
Restructuring Cost and Reserve
Ending balance			$ 394us-gaap_RestructuringReserve
Pre-2012 Activities
Restructuring Cost and Reserve
Beginning Balance	1,084
Change in estimate	(553)
Cash payments	(531)
Q2 2012 Activity
Restructuring Cost and Reserve
Provision		286
Change in estimate		(4)
Cash payments		(282)
Q3 2012 Activity
Restructuring Cost and Reserve
Beginning Balance	243
Provision		687
Cash payments	(243)	(444)
Ending balance		243
Q3 2013 Activity
Restructuring Cost and Reserve
Beginning Balance			371
Provision	1,337
Cash payments	(966)		(371)
Ending balance	371
Q4 2013 Activity
Restructuring Cost and Reserve
Beginning Balance			114
Provision	600
Cash payments	(486)		(114)
Ending balance	114
Q2 2014 Activity
Restructuring Cost and Reserve
Provision			572
Cash payments			(572)
Q3 2014 Activity
Restructuring Cost and Reserve
Provision			225
Cash payments			(225)
Q4 2014 Activity
Restructuring Cost and Reserve
Provision			826
Cash payments			(432)
Ending balance			394
Severance and Benefits
Restructuring Cost and Reserve
Ending balance			394
Severance and Benefits \| Q2 2012 Activity
Restructuring Cost and Reserve
Provision		286
Change in estimate		(4)
Cash payments		(282)
Severance and Benefits \| Q3 2012 Activity
Restructuring Cost and Reserve
Beginning Balance	243
Provision		687
Cash payments	(243)	(444)
Ending balance		243
Severance and Benefits \| Q3 2013 Activity
Restructuring Cost and Reserve
Beginning Balance			371
Provision	1,337
Cash payments	(966)		(371)
Ending balance	371
Severance and Benefits \| Q4 2013 Activity
Restructuring Cost and Reserve
Beginning Balance			114
Provision	600
Cash payments	(486)		(114)
Ending balance	114
Severance and Benefits \| Q2 2014 Activity
Restructuring Cost and Reserve
Provision			572
Cash payments			(572)
Severance and Benefits \| Q3 2014 Activity
Restructuring Cost and Reserve
Provision			225
Cash payments			(225)
Severance and Benefits \| Q4 2014 Activity
Restructuring Cost and Reserve
Provision			826
Cash payments			(432)
Ending balance			394
Facility Exit Costs \| Pre-2012 Activities
Restructuring Cost and Reserve
Beginning Balance	1,084
Change in estimate	(553)
Cash payments	$ (531)