Indebtedness - Schedule of Net Carrying Amount of Liability Component (Details) - 2027 Notes - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Principal amount	$ 200,000	$ 200,000
Unamortized debt discount	(54,562)	(56,080)
Unamortized debt issuance cost	(270)	(278)
Long-term debt	$ 145,168	$ 143,642

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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount, after accumulated amortization, of debt discount.

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Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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