Convertible Senior Notes - Future Minimum Payments (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Principal repayments
Convertible senior notes	$ 140,415	$ 139,966
Convertible senior notes
Principal repayments
2022	1,886
2023	3,773
2024	3,773
2025	3,773
2026	145,638
Total minimum payments	158,843
Less: interest	(15,093)
Less: unamortized issuance costs	(3,335)
Convertible senior notes	$ 140,415

Total minimum payments of debt instrument.

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Carrying value as of the balance sheet date of long-term debt (with maturities initially due after one year or beyond the operating cycle if longer) identified as Convertible Notes Payable, excluding current portion. Convertible Notes Payable is a written promise to pay a note which can be exchanged for a specified amount of another, related security, at the option of the issuer and the holder.

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Amount of unamortized debt discount (premium) and debt issuance costs.

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Amount of interest payable on debt, including, but not limited to, trade payables.

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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