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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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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Net Loss Per Share (Details) - shares	3 Months Ended		6 Months Ended
Net Loss Per Share (Details) - shares	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Securities Excluded from Calculations of Earnings Per Share Because Impact Would Have Been Anti-Dilutive [Abstract]
Outstanding securities used in calculations (in shares)	1,589,715,000	738,093,000	1,557,513,000	730,485,000
Conversion features under term loan facility
Potential Dilutive Effect of Securities [Abstract]
Conversion of Deerfield Warrants (in shares)			11,996,038	0
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)	0	21,290,000	0	25,161,000
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)	3,579,000	12,599,000	3,107,000	12,235,000
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)	64,134,000	57,203,000	32,404,000	46,088,000
Warrants
Securities Excluded from Calculations of Earnings Per Share Because Impact Would Have Been Anti-Dilutive [Abstract]
Outstanding securities used in calculations (in shares)	1,522,002,000	647,001,000	1,522,002,000	647,001,000
Convertible notes
Potential Dilutive Effect of Securities [Abstract]
Conversion of the Notes (in shares)			8,463,236	1,193,938