Net Income (Loss) per Share - Computation of Denominators Used in Net Loss per Share (Detail) - shares	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Basic:
Weighted average common shares outstanding - Basic	50,114,710	46,885,424	50,031,615	46,803,659
Diluted:
Weighted average common shares outstanding - Basic	50,114,710	46,885,424	50,031,615	46,803,659
Common stock equivalents	0	0	0	0
Denominator for diluted net loss per share	50,114,710	46,885,424	50,031,615	46,803,659