Balance Sheet Information - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2015
Property, Plant and Equipment [Line Items]
Allowance for doubtful accounts	$ 264		$ 264		$ 314
Consigned inventory with customers	500		500		700
Allowance for inventory losses	2,800		2,800		$ 2,200
Depreciation and amortization	$ 800	$ 800	$ 1,600	$ 1,500
Equipment [Member]
Property, Plant and Equipment [Line Items]
Period over which assets are depreciated			5 years
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Period over which assets are depreciated			7 years
Building [Member]
Property, Plant and Equipment [Line Items]
Period over which assets are depreciated			30 years
Minimum [Member]
Property, Plant and Equipment [Line Items]
Standard term of accounts receivable			30 days
Minimum [Member] | Computer Equipment [Member]
Property, Plant and Equipment [Line Items]
Period over which assets are depreciated			3 years
Maximum [Member]
Property, Plant and Equipment [Line Items]
Standard term of accounts receivable			60 days
Useful lives of the assets			1 year
Maximum [Member] | Computer Equipment [Member]
Property, Plant and Equipment [Line Items]
Period over which assets are depreciated			5 years