Long-term Debt - Summary of Long-term Debt (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Total debt	$ 178,668	$ 183,537
Less: Current portion	(18,234)	(17,778)
Long-term debt	160,434	165,759
Unamortized debt issuance costs	2,900	600
4.75% Convertible Senior Notes
Debt Instrument [Line Items]
Total debt	131,071	0
Long-term debt, gross	135,000
1.5% Convertible Unsecured Senior Notes
Debt Instrument [Line Items]
Total debt	25,765	143,242
Long-term debt, gross	26,000	157,400
Promissory note
Debt Instrument [Line Items]
Total debt	17,534	17,095
Other debt and finance lease obligations
Debt Instrument [Line Items]
Total debt	4,298	4,792
Revolving Credit Facility
Debt Instrument [Line Items]
Total debt	$ 0	$ 18,408

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.

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