Unsecured Convertible Senior Notes - Future minimum payments (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Long-term Debt, Fiscal Year Maturity [Abstract]
Total future minimum principal payments under 2023 Notes and 2026 Notes	$ 320,030	$ 320,030
2023 and 2026 Convertible Senior Notes
Long-term Debt, Fiscal Year Maturity [Abstract]
2023	95,000
2026	225,030
Total future minimum principal payments under 2023 Notes and 2026 Notes	$ 320,030

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant