Convertible Senior Notes - Notes Payable (Details) - Convertible Notes - 2023 Convertible Senior Notes - USD ($)	Jun. 30, 2022	Dec. 31, 2021	May 31, 2018
Notes Payable, Current and Noncurrent [Abstract]
Principal amount of the 2023 Notes outstanding	$ 115,499,000	$ 343,301,000	$ 750,000,000
Unamortized discount (including unamortized debt issuance cost)	(525,000)	(22,584,000)
Total long-term portion of notes payable	114,974,000	320,717,000
Fair value of the 2023 Notes outstanding (Level 2)	$ 110,590,000	$ 341,801,000

Amount, after accumulated amortization, of debt discount (premium).

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Balance Type:	debit
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