Net Loss Per Share (Details) - $ / shares	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Warrant, exercise price (in dollars per share)	$ 75.90
Warrant, exercise period (in years)	5 years
Stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive stock options outstanding (in shares)	1,364,000	989,000
Restricted Stock Unit Awards
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive stock options outstanding (in shares)	468,000	375,000
Convertible Debt Securities \| Convertible Notes \| Convertible Senior Notes due 2024
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive stock options outstanding (in shares)	638,051
Initial conversion price (in dollars per share)	$ 46.4037
Convertible Debt Securities \| Convertible Notes \| Convertible Senior Notes Due 2026
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive stock options outstanding (in shares)	3,700,272
Initial conversion price (in dollars per share)	$ 30.8356
Convertible Debt Securities \| Convertible Notes \| Convertible Senior Notes Due 2027
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive stock options outstanding (in shares)	4,732,132
Initial conversion price (in dollars per share)	$ 17.8571

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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