Segment, Customer Concentration and Geographical Information - Company Revenue in Different Geographic Locations (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Revenue from External Customer [Line Items]
Total revenues	$ 7,459	$ 9,386	$ 14,673	$ 19,915
Americas [Member]
Revenue from External Customer [Line Items]
Total revenues	7,302	9,253	14,444	19,565
EMEA [Member]
Revenue from External Customer [Line Items]
Total revenues	103	73	164	125
Asia Pacific [Member]
Revenue from External Customer [Line Items]
Total revenues	$ 54	$ 60	$ 65	$ 225