Earnings Per Share - Components of Basic and Diluted Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Earnings Per Share [Abstract]
Net income (loss)	$ 9,702	$ (23,940)	$ (31,466)	$ (267,509)
Weighted average common shares outstanding (in shares)	34,484	33,906	34,314	34,058
Effect of dilutive securities:
Stock options and RSUs	236	0	0	0
Shares used in calculating dilutive net income (loss) per share (in shares)	34,720	33,906	34,314	34,058
Net income (loss) per share:
Basic (in dollars per share)	$ 0.28	$ (0.71)	$ (0.92)	$ (7.85)
Diluted (in dollars per share)	$ 0.28	$ (0.71)	$ (0.92)	$ (7.85)