Net Loss Per Share - Net Loss Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Numerator:
Net loss available to common stockholders	$ (2,232)	$ (3,706)
Denominator:
Weighted average shares outstanding - basic	12,163	11,524
Weighted average shares outstanding - diluted	12,163	11,524
Shares excluded due to an exercise price greater than weighted average stock price for the period	1,908	401
Net loss per common share:
Basic	$ (0.18)	$ (0.32)
Diluted	$ (0.18)	$ (0.32)