Net Loss per Share - Additional Information (Details) - $ / shares	Dec. 31, 2019	Sep. 30, 2019
Pre-funded Warrants
Class Of Warrant Or Right [Line Items]
Exercise price of warrants	$ 0.01
Private Placement \| Institutional Accredited Investors
Class Of Warrant Or Right [Line Items]
Exercise price of warrants	$ 0.65	$ 0.65
Private Placement \| Institutional Accredited Investors \| Pre-funded Warrants
Class Of Warrant Or Right [Line Items]
Issuance of warrants, shares	5,411,687	5,411,687
Number of securities called by warrants	5,411,687	5,411,687
Exercise price of warrants	$ 0.64	$ 0.64
Exercise price of warrants, exercisable subject to beneficial ownership limitations	$ 0.01	$ 0.01

Class of warrant or right issued.

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- Definition

Exercise price of warrants or rights exercisable subject to beneficial ownership limitations.

+ References

No definition available.

+ Details

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(i)(4))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ 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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- Definition

Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(i)(2))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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- Details

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