Net Loss Per Common Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Earnings Per Share [Abstract]
Net loss	$ (13,415)	$ (6,386)	$ (31,064)	$ (10,061)
Basic weighted-average common shares outstanding (in shares)	67,623	66,820	67,409	49,858
Basic loss per common share (in dollars per share)	$ (0.20)	$ (0.10)	$ (0.46)	$ (0.20)
Diluted loss per common share (in dollars per share)	$ (0.20)	$ (0.10)	$ (0.46)	$ (0.20)
Antidilutive securities excluded from diluted net income per common share (in shares)	3,051	2,588	3,051	1,657