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Debt - Components (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Jun. 30, 2020	May 12, 2020	Dec. 31, 2019	Aug. 23, 2017
Debt Instrument [Line Items]
Fair value of embedded derivative	$ 4,900		$ 4,600
Term loan \| Secured debt
Debt Instrument [Line Items]
Principal amount				$ 47,500
Unamortized debt discount					$ (4,000)
Unamortized debt discount and debt issuance costs				(962)
Net carrying amount				46,538
2025 Notes \| Convertible debt
Debt Instrument [Line Items]
Principal amount	166,898
Fair value of embedded derivative	4,898
Unamortized debt discount	(3,703)
Unamortized issuance costs	(2,946)
Net carrying amount	$ 165,147
2022 Notes \| Convertible debt
Debt Instrument [Line Items]
Principal amount		$ 2	$ 45,000	105,125
Unamortized debt discount and debt issuance costs				(3,791)
Net carrying amount				$ 101,334