Net Loss Per Share - Computation of basic and diluted net loss per share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Earnings Per Share [Abstract]
Net loss	$ (8,418)	$ (10,669)
Net loss from continuing operations	(8,418)	(10,390)
Loss from discontinued operations, net of taxes	$ 0	$ (279)
Weighted average common shares outstanding, basic and diluted (in shares)	98,581	107,024
Continuing operations (in dollars per share)	$ (0.09)	$ (0.10)
Discontinuing operations (in dollars per share)	$ 0.00	$ 0.00