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Long-term Debt - Convertible Senior Notes Carrying Value (Details) - Senior Notes - USD ($)	Sep. 30, 2023	Dec. 31, 2022	Aug. 31, 2020	Oct. 31, 2018	Oct. 24, 2018	Oct. 22, 2018
2024 Notes
Debt Instrument [Line Items]
Carrying value	$ 991,000	$ 23,925,000
Unamortized debt discount and issuance costs	9,000	356,000
Principal amount	$ 1,000,000	$ 24,281,000	$ 117,100,000
Remaining amortization period (years)	0 years	1 year 10 months 24 days
2024 Notes \| Level 2
Debt Instrument [Line Items]
Fair value		$ 38,000,000
2025 Notes
Debt Instrument [Line Items]
Carrying value	$ 169,848,000	168,885,000
Unamortized debt discount and issuance costs	2,652,000	3,615,000
Principal amount	$ 172,500,000	$ 172,500,000		$ 172,500,000	$ 22,500,000	$ 150,000,000
Remaining amortization period (years)	2 years	2 years 9 months 18 days
2025 Notes \| Level 2
Debt Instrument [Line Items]
Fair value	$ 183,066,000	$ 185,546,000