Net Loss Per Share - Computation of Basic and Diluted Net Loss Per Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Numerator:
Net loss	$ (9,078)	$ (1,797)
Denominator:
Weighted average shares outstanding, basic and diluted	23,257,541	23,063,471
Net loss per share, basic and diluted	$ (0.39)	$ (0.08)