Convertible Notes Payable - Summary of Outstanding Balances of Convertible Notes (Details) - Convertible debt - 3.00% Convertible notes - USD ($) $ in Thousands	Sep. 30, 2020	Sep. 17, 2019
Debt Instrument [Line Items]
Principal	$ 305,000	$ 305,000
Less: debt discount and issuance costs, net	(96,098)
Net carrying amount	208,902	166,300
Equity component	$ 134,450	$ 138,700

Long Term Debt, Gross Excluding Interest

No definition available.

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- Definition

The carrying amount of the equity component of convertible debt which may be settled in cash upon conversion.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
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- Definition

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.

+ References

No definition available.

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- Definition

Amount of unamortized debt discount (premium) and debt issuance costs.

+ References

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- Definition

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.

+ References

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)(3)
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Section S99
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