Acquisitions - Restructuring Accrued Liability (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Mar. 31, 2013	Jun. 30, 2013
Restructuring Cost and Reserve [Line Items]
Beginning Balance	$ 910	$ 1,658	$ 1,658
Cash payments or other settlements	(398)	(748)
Ending Balance	512	910	512
Total incurred and expected charges			5,777
Severance and Other-Related Costs [Member]
Restructuring Cost and Reserve [Line Items]
Beginning Balance	691	1,397	1,397
Cash payments or other settlements	(365)	(706)
Ending Balance	326	691	326
Total incurred and expected charges			5,377
Other [Member]
Restructuring Cost and Reserve [Line Items]
Beginning Balance	219	261	261
Cash payments or other settlements	(33)	(42)
Ending Balance	186	219	186
Total incurred and expected charges			$ 400