Convertible Senior Notes Due 2023 - Summary of liability component of 2023 Notes (Details) - USD ($)	Dec. 31, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Total carrying value	$ 379,252,000	$ 361,751,000
Convertible Debt
Debt Instrument [Line Items]
2023 Notes	402,500,000	402,500,000
Unamortized debt discount and deferred financing costs	(23,248,000)	(40,749,000)
Total carrying value	$ 379,252,000	$ 361,751,000

Face (par) amount of debt instrument at time of issuance.

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