Acquisition - Additional Information (Detail) - USD ($) $ in Thousands		9 Months Ended
	May. 08, 2015	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Business Acquisition [Line Items]
Cash paid for acquisition, net of cash acquired		$ 19,259	$ 4,121
Fair value of net tangible and identifiable intangible assets acquired		$ 33,461		$ 20,802
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Business Acquisition [Line Items]
Business acquisition date		May 08, 2015
Business acquisition interest acquired, percentage	100.00%
Acquisition of business for total consideration	$ 22,200
Cash paid for acquisition, net of cash acquired	1,900
Purchase consideration, cash paid at closing	19,200
Cash withheld to cover potential net working capital	1,100
Fair value of net tangible and identifiable intangible assets acquired	$ 12,558
Acquisition related costs		$ 200