Calculations for Basic and Diluted Net Income (Loss) Per Common Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Numerator:
Net income (loss)	$ 2,466	$ (2,749)	$ 1,001	$ (4,796)
Accretion of Series B convertible preferred stock dividends	(286)	(272)	(570)	(543)
Net income (loss) available to common stockholders	$ 2,180	$ (3,021)	$ 431	$ (5,339)
Denominator:
Weighted average common shares outstanding - basic	21,908	17,941	20,185	17,730
Net income (loss) per common share - basic	$ 0.10	$ (0.17)	$ 0.02	$ (0.30)
Dilutive securities:
Stock options, RSUs, PSUs, and warrants	958		907
Convertible preferred shares	5,885
Weighted average common shares outstanding - diluted	28,751	17,941	21,092	17,730
Net income (loss) per common share - diluted	$ 0.09	$ (0.17)	$ 0.02	$ (0.30)
Diluted net income (loss) per common share:
Net income (loss) available to common stockholders	$ 2,180	$ (3,021)	$ 431	$ (5,339)
Plus: accretion of Series B convertible preferred stock dividends, if dilutive	286
Net income (loss) available to common stockholders	$ 2,466	$ (3,021)	$ 431	$ (5,339)