Description of Business and Basis of Presentation (Net Income (Loss) per Share) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Numerator:
Loss from continuing operations	$ (17,620)	$ (10,514)
Less: Income from discontinued operations, net of income taxes	0	1,309
Net loss	$ (17,620)	$ (9,205)
Denominator:
Continuing operations	$ (0.38)	$ (0.28)
Discontinued operations	$ 0.00	$ 0.03
Basic and diluted (in shares)	46,220	37,522
Net income (loss) per share - basic and diluted:
Basic and diluted (in dollars per share)	$ (0.38)	$ (0.25)