Debt - Convertible Notes Balances (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Apr. 30, 2020
Equity component, net of issuance costs		$ 85,600
Convertible Notes
Debt principal balance	$ 287,500
Unamortized debt discount and debt issuance cost	(85,007)
Net carrying amount	$ 202,493
Equity component, net of issuance costs		$ 85,600

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Name:	us-gaap_DebtInstrumentCarryingAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant