Net Income Per Common Share - Reconciliation of Numerator and Denominator Used in Calculation of Basic and Diluted Net Income Per Common Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Numerator:
Net income	$ 1,810	$ 2,207
Basic:
Weighted average shares of common stock and vested, undelivered restricted stock units outstanding	28,140,619	28,003,663
Diluted:
Weighted average shares of common stock and vested, undelivered restricted stock units outstanding	28,140,619	28,003,663
Effect of potentially dilutive shares	1,101,728	436,056
Total weighted average shares of common stock and vested, undelivered restricted stock units outstanding and potentially dilutive shares	29,242,347	28,439,719
Basic:
Net income applicable to common stockholders	$ 1,810	$ 2,207
Weighted average shares of stock outstanding	28,140,619	28,003,663
Basic net income per common share	$ 0.06	$ 0.08
Diluted:
Net income applicable to common stockholders	$ 1,810	$ 2,207
Weighted average shares of stock outstanding	29,242,347	28,439,719
Diluted net income per common shares	$ 0.06	$ 0.08