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Long-term Debt - Convertible Senior Notes Carrying Value (Details) - Senior Notes - USD ($)	6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021	Aug. 31, 2020	Oct. 31, 2018	Oct. 24, 2018	Oct. 22, 2018
2024 Notes
Debt Instrument [Line Items]
Convertible Debt, Total	$ 114,893,000		$ 89,361,000
Unamortized debt discount and issuance costs	2,158,000		27,690,000
Principal amount	$ 117,051,000		117,051,000	$ 117,100,000
Remaining amortization period (years)	2 years 4 months 24 days	2 years 10 months 24 days
2024 Notes \| Level 2
Debt Instrument [Line Items]
Fair value	$ 197,477,000		195,445,000
2025 Notes
Debt Instrument [Line Items]
Convertible Debt, Total	168,245,000		126,315,000
Unamortized debt discount and issuance costs	4,255,000		46,185,000
Principal amount	$ 172,500,000		172,500,000		$ 172,500,000	$ 22,500,000	$ 150,000,000
Remaining amortization period (years)	3 years 3 months 18 days	3 years 9 months 18 days
2025 Notes \| Level 2
Debt Instrument [Line Items]
Fair value	$ 195,434,000		$ 177,251,000