Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Basic and Diluted Earnings per Share
Net loss from continuing operations	$ (120,827)	$ (25,817)	$ (242,911)	$ (83,916)
Net income from discontinued operations	0	5,736	0	9,592
Net loss	$ (120,827)	$ (20,081)	$ (242,911)	$ (74,324)
Weighted average common shares outstanding (in shares)	33,807	34,358	34,136	34,261
Basic and diluted net (loss) income per share:
Loss from continuing operations (in dollars per share)	$ (3.57)	$ (0.75)	$ (7.12)	$ (2.45)
Income (loss) from discontinued operations (in dollars per share)	0	0.17	0	0.28
Basic and diluted net loss per share (in dollars per share)	$ (3.57)	$ (0.58)	$ (7.12)	$ (2.17)
Anti-dilutive securities (in shares)			17,242	18,801
Options to purchase shares of common stock
Basic and diluted net (loss) income per share:
Anti-dilutive securities (in shares)			3,926	3,893
Shares of common stock issuable upon the vesting of RSUs
Basic and diluted net (loss) income per share:
Anti-dilutive securities (in shares)			1,621	1,415
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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