Schedule of Changes in Level 3 Contingent Consideration Liability Measured on Recurring Basis (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015
Business Acquisition, Contingent Consideration [Line Items]
Beginning balance	$ 3,603
Fair value adjustment	(48)
Ending balance	951
Level 3
Business Acquisition, Contingent Consideration [Line Items]
Beginning balance	3,603
Fair value adjustment	48
Payment	(2,700)
Ending balance	$ 951