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Convertible Senior Notes - Carrying Value of 2026 Notes (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Sep. 30, 2021	Feb. 05, 2021
Debt Instrument [Line Items]
2026 Notes embedded conversion derivative	$ 42,821	$ 48,208
Convertible Debt \| 2026 Notes
Debt Instrument [Line Items]
Principal amount	155,250
Less: unamortized discount and issuance costs, net of amortization	(32,618)
Carrying amount	122,632
Convertible Debt \| 2026 Notes \| Embedded conversion derivative
Debt Instrument [Line Items]
Less: unamortized discount and issuance costs, net of amortization	(32,600)
2026 Notes embedded conversion derivative	$ 42,821		$ 33,200