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, 2020	Mar. 31, 2019
Numerator:
Net income	$ 2,207	$ 3,290
Basic:
Weighted average shares of common stock and vested, undelivered restricted stock units outstanding	28,003,663	27,804,835
Diluted:
Weighted average shares of common stock and vested, undelivered restricted stock units outstanding	28,003,663	27,804,835
Effect of potentially dilutive shares	436,056	401,118
Total weighted average shares of common stock and vested, undelivered restricted stock units outstanding and potentially dilutive shares	28,439,719	28,205,953
Net Income Per Share:
Basic net income per share	$ 0.08	$ 0.12
Diluted net income per share	$ 0.08	$ 0.12