Including the current and noncurrent portions, carrying amount of debt identified as being convertible into another form of financial instrument (typically the entity's common stock) as of the balance sheet date, which originally required full repayment more than twelve months after issuance or greater than the normal operating cycle of the company.

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Long-term Debt - Convertible Senior Notes Carrying Value (Details) - Senior Notes - USD ($)	3 Months Ended
	Mar. 31, 2022	Mar. 31, 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	$ 114,672,000		$ 89,361,000
Unamortized debt discount and issuance costs	2,379,000		27,690,000
Principal amount	$ 117,051,000		117,051,000	$ 117,100,000
Remaining amortization period (years)	2 years 8 months 12 days	2 years 10 months 24 days
2024 Notes \| Level 2
Debt Instrument [Line Items]
Fair value	$ 209,973,000		195,445,000
2025 Notes
Debt Instrument [Line Items]
Convertible Debt, Total	167,926,000		126,315,000
Unamortized debt discount and issuance costs	4,574,000		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 6 months	3 years 9 months 18 days
2025 Notes \| Level 2
Debt Instrument [Line Items]
Fair value	$ 203,648,000		$ 177,251,000