Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Basic and Diluted Earnings per Share
Net loss from continuing operations	$ (23,617)	$ (64,678)	$ (266,528)	$ (148,592)
Net income from discontinued operations	0	95,517	0	105,108
Net (loss) income	$ (23,617)	$ 30,839	$ (266,528)	$ (43,484)
Weighted average common shares outstanding (in shares)	33,906	34,492	34,058	34,339
Basic and diluted net (loss) income per share:
Loss from continuing operations (in dollars per share)	$ (0.70)	$ (1.88)	$ (7.83)	$ (4.33)
Income from discontinued operations (in dollars per share)	0	2.77	0	3.06
Basic and diluted net (loss) income per share (in dollars per share)	$ (0.70)	$ 0.89	$ (7.83)	$ (1.27)
Anti-dilutive securities (in shares)			17,328	18,328
Options to purchase shares of common stock
Basic and diluted net (loss) income per share:
Anti-dilutive securities (in shares)			3,988	3,700
Shares of common stock issuable upon the vesting of RSUs
Basic and diluted net (loss) income per share:
Anti-dilutive securities (in shares)			1,645	1,135
Warrants
Basic and diluted net (loss) income per share:
Anti-dilutive securities (in shares)			0	1,008
2022 Convertible Notes \| Convertible Debt Securities
Basic and diluted net (loss) income per share:
Anti-dilutive securities (in shares)			11,695	11,695
2019 Convertible Notes \| Convertible Debt Securities
Basic and diluted net (loss) income per share:
Anti-dilutive securities (in shares)			0	790

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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