Information Regarding Net Revenue by Geographic Region (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Segment Reporting Information [Line Items]
Net revenue	$ 15,560	$ 17,196	$ 41,521	$ 47,717
Percentage of net revenue	100.00%	100.00%	100.00%	100.00%
Americas
Segment Reporting Information [Line Items]
Net revenue	$ 9,924	$ 12,473	$ 27,343	$ 32,423
Percentage of net revenue	64.00%	73.00%	66.00%	68.00%
Europe And Middle East
Segment Reporting Information [Line Items]
Net revenue	$ 2,834	$ 2,294	$ 6,654	$ 7,386
Percentage of net revenue	18.00%	13.00%	16.00%	15.00%
Asia-Pacific
Segment Reporting Information [Line Items]
Net revenue	$ 2,802	$ 2,429	$ 7,524	$ 7,908
Percentage of net revenue	18.00%	14.00%	18.00%	17.00%