Stockholders' Equity - Summary of Pre-funded Warrants for Common Stock Issued and Outstanding (Details) - Pre-funded Warrants	3 Months Ended
Mar. 31, 2021 $ / shares shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Warrants Outstanding	16,610,328
February 8, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Issue Date	Feb. 08, 2019
Expiration Date	None
Exercise Price \| $ / shares	$ 0.0001
Number of Warrants Outstanding	3,750,000
April 30, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Issue Date	Apr. 30, 2020
Expiration Date	None
Exercise Price \| $ / shares	$ 0.0001
Number of Warrants Outstanding	12,860,328

Warrant expiration date.

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- Definition

Date the warrants or rights are exercisable, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21475-112644

+ Details

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- Definition

Exercise price per share or per unit of warrants or rights outstanding.

+ References

+ Details

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- Definition

Number of warrants or rights outstanding.

+ References

No definition available.

+ Details

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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.

+ Details

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