Quarterly Financial Data (Unaudited) - Summary of Quarterly Financial Data (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended																12 Months Ended
	Dec. 31, 2015		Sep. 30, 2015		Jun. 30, 2015		Mar. 31, 2015		Dec. 31, 2014		Sep. 30, 2014		Jun. 30, 2014		Mar. 31, 2014		Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Quarterly Financial Information Disclosure [Abstract]
Revenue	$ 47,003		$ 42,996		$ 46,633		$ 48,647		$ 53,627		$ 51,013		$ 53,167		$ 49,173		$ 185,279	$ 206,980	$ 204,724
Gross profit	31,135		28,479		27,527		32,943		37,690		36,306		36,120		33,294		120,084	143,410	124,322
Total operating expenses	36,941		193,427		30,354		31,801		34,717		34,574		34,279		37,996		292,523	141,566	197,755
Net loss	$ (9,903)		$ (160,265)		$ (3,947)		$ (4,561)		$ (273)		$ (3,041)		$ (2,895)		$ (6,673)		$ (178,676)	$ (12,882)	$ (82,227)
Net loss per basic share (in dollars per share)	$ (0.10)	[1]	$ (1.61)	[1]	$ (0.04)	[1]	$ (0.05)	[1]	$ 0.00	[1]	$ (0.03)	[1]	$ (0.03)	[1]	$ (0.07)	[1]	$ (1.79)	$ (0.13)	$ (0.85)
Net loss per diluted share (in dollars per share)	$ (0.10)	[1]	$ (1.61)	[1]	$ (0.04)	[1]	$ (0.05)	[1]	$ (0.03)	[1]	$ (0.04)	[1]	$ (0.03)	[1]	$ (0.07)	[1]	$ (1.79)	$ (0.16)	$ (0.85)

[1] Basic and diluted net loss per share is computed independently for each of the quarters presented. Therefore, the sum of the quarterly per share amounts will not necessarily equal the total for the year.