Loss Per Share - Summary of Basic and Diluted Loss Per Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Basic and diluted loss per share:
Net loss	$ (49,926)	$ (54,014)
Weighted average common shares outstanding - basic	42,529,017	42,529,017
Weighted average common shares outstanding - diluted	42,529,017	42,529,017
Basic loss per share	$ (1.17)	$ (1.27)
Diluted loss per share	$ (1.17)	$ (1.27)
Common share equivalents excluded due to anti-dilutive effect	3,788,388