Convertible Senior Notes - Summary of total gross principal payments due under the Convertible notes payable (Details)	6 Months Ended
Jun. 30, 2020 USD ($)
Convertible Senior Notes
2025	$ 115,000,000
Total Payments	$ 115,000,000

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
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-Section 50
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant