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Debt - Components (Details) - USD ($)	Jun. 30, 2020	May 12, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Fair value of embedded derivative	$ 3,800,000	$ 4,600,000
Term Loan \| Secured Debt
Debt Instrument [Line Items]
Principal amount			$ 47,500,000
Unamortized debt discount and debt issuance costs			(962,000)
Net carrying amount			46,538,000
2025 Notes \| Convertible Debt
Debt Instrument [Line Items]
Principal amount	180,375,000	180,400,000
Fair value of embedded derivative	3,756,000
Unamortized debt discount	(4,458,000)
Unamortized issuance costs	(3,502,000)
Net carrying amount	176,171,000
2022 Notes \| Convertible Debt
Debt Instrument [Line Items]
Principal amount	2,000	$ 45,000,000.0	105,125,000
Unamortized debt discount and debt issuance costs	0		(3,791,000)
Net carrying amount	$ 2,000		$ 101,334,000