Net Loss Per Share (Details) - shares	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Securities Excluded from Calculations of Earnings Per Share Because Impact Would Have Been Anti-Dilutive [Abstract]
Outstanding securities used in calculations (in shares)	1,596,037	44,866	88,932
Conversion features under term loan facility
Potential Dilutive Effect of Securities [Abstract]
Conversion of Deerfield Warrants (in shares)	10,486,604	1,522,002	647,001
Convertible notes
Potential Dilutive Effect of Securities [Abstract]
Conversion of the Notes (in shares)	8,211,088	755,695	1,193,938
Common stock options
Securities Excluded from Calculations of Earnings Per Share Because Impact Would Have Been Anti-Dilutive [Abstract]
Outstanding securities used in calculations (in shares)	62	11,276	52,029
Restricted stock awards
Securities Excluded from Calculations of Earnings Per Share Because Impact Would Have Been Anti-Dilutive [Abstract]
Outstanding securities used in calculations (in shares)	3,501	11,616	11,898
Restricted stock units
Securities Excluded from Calculations of Earnings Per Share Because Impact Would Have Been Anti-Dilutive [Abstract]
Outstanding securities used in calculations (in shares)	70,472	21,974	25,005
Warrants
Securities Excluded from Calculations of Earnings Per Share Because Impact Would Have Been Anti-Dilutive [Abstract]
Outstanding securities used in calculations (in shares)	1,522,002	0	0

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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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of call options and warrants using the treasury stock method.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of convertible debt securities using the if-converted method.

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