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Contractual interest rate for funds borrowed, under the debt agreement.

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Debt - Schedule of Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Feb. 28, 2021	Dec. 31, 2020	Nov. 30, 2019	Mar. 31, 2018	Feb. 28, 2014
Convertible Debt
Debt Instrument [Line Items]
Net carrying value of all Notes	$ 54,160		$ 54,224
Secured Debt
Debt Instrument [Line Items]
Interest rate on notes	4.00%
Principal amount	$ 10,000		0
End of term fee accretion	79		0
Unamortized debt issuance cost	(30)		0
Net carrying value of all Notes	10,049		0
Line of Credit \| Revolving Credit Facility
Debt Instrument [Line Items]
Borrowing Base	9,368		15,000
Carrying value of advances under revolving credit agreement	6,838		0
2014 Notes \| Convertible Debt
Debt Instrument [Line Items]
Interest rate on notes						2.75%
Principal amount	578	$ 500	1,079		$ 51,300
Unamortized debt discount	(8)		(16)
Unamortized debt issuance cost	(2)		(4)			$ (1,100)
Net carrying value of all Notes	568		1,059
2019 Notes \| Convertible Debt
Debt Instrument [Line Items]
Interest rate on notes				5.25%
Principal amount	55,000	$ 500	55,000
Unamortized debt issuance cost	(1,408)		(1,835)
Net carrying value of all Notes	$ 53,592		$ 53,165