Earnings Per Share - Details of Basic and Diluted Earnings (Loss) Per Share (EPS) (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Earnings Per Share [Abstract]
Net income (loss)	$ 21,298	$ (21,541)	$ (177,604)
Weighted average common shares outstanding used in basic EPS	44,339	44,132	43,768
Common shares issuable upon exercise of dilutive stock options and PSAs / RSUs	275
Weighted average common shares outstanding and common share equivalents used in diluted EPS	44,614	44,132	43,768
Earnings (loss) per share
Continuing operations	$ 0.47	$ (0.57)	$ (0.01)
Discontinued operations	$ 0.01	$ 0.08	$ (4.05)