Net Income (Loss) per Share - Computation of Basic and Diluted Net Income (Loss) Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ 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
Earnings Per Share [Abstract]
Net income (loss)	$ (1,473)	$ (125)	$ (176)	$ (761)	$ 1,047	$ (291)	$ 274	$ 102	$ (2,535)	$ 1,132	$ 2,033
Deemed dividends on preferred stock									40
Amortization of preferred stock beneficial conversion feature									82
NET INCOME (LOSS) ATTRIBUTABLE TO COMMON STOCKHOLDERS	$ (1,595)	$ (125)	$ (176)	$ (761)					$ (2,657)	$ 1,132	$ 2,033
Basic weighted average common shares outstanding	60,859	60,537	60,425	60,277	60,043	54,444	49,890	49,277	60,526	53,483	48,263
Effect of potentially dilutive securities										2,533	4,512
Diluted weighted average shares outstanding	60,859	60,537	60,425	60,277	62,732	54,444	53,733	53,469	60,526	56,016	52,775
Basic net income (loss) per share attributable to common stockholders									$ (0.04)	$ 0.02	$ 0.04
Diluted net income (loss) per share									$ (0.04)	$ 0.02	$ 0.04