Geographic, Customer and Supplier Information - Sales Details of Customers Locations in Four Geographic Regions (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Geographic And Business Segment Information [Line Items]
Revenue	$ 47,597	$ 43,648	$ 54,293	$ 46,767	$ 50,889	$ 60,027	$ 65,393	$ 65,135	$ 192,304	$ 241,443	$ 201,537
Gross profit	31,954	$ 30,050	$ 36,551	$ 32,104	33,000	$ 35,695	$ 37,739	$ 37,106	130,657	143,540	125,642
Long-lived assets	7,721				3,461				7,721	3,461	3,194
Europe, Middle East, Africa (EMEA) [Member]
Geographic And Business Segment Information [Line Items]
Revenue									100,858	164,180	129,385
Gross profit									65,025	92,721	78,933
Long-lived assets	7,005				2,771				7,005	2,771	2,815
United States [Member]
Geographic And Business Segment Information [Line Items]
Revenue									23,603	11,723	12,098
Gross profit									20,555	9,766	10,143
Long-lived assets	632				620				632	620	275
Asia Pacific [Member]
Geographic And Business Segment Information [Line Items]
Revenue									52,871	47,156	42,365
Gross profit									34,202	28,508	23,996
Long-lived assets	26				19				26	19	31
Other Countries [Member]
Geographic And Business Segment Information [Line Items]
Revenue									14,972	18,384	17,689
Gross profit									10,874	12,545	13,360
Long-lived assets	$ 58				$ 51				$ 58	$ 51	$ 73