Quarterly report pursuant to Section 13 or 15(d)

Cover
- Document and Entity Information
Financial Statements
Notes to Financial Statements
Accounting Policies
- Summary of Significant Accounting Policies (Policies)
Notes Tables
Notes Details

Basis of Presentation - Additional Information (Details)

v3.19.3

Basis of Presentation - Additional Information (Details)				3 Months Ended		9 Months Ended		12 Months Ended
	Jun. 26, 2018 USD ($) $ / shares shares	May 30, 2018 USD ($) $ / shares shares	May 15, 2018 $ / shares	Sep. 30, 2019 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2018 USD ($)	Dec. 31, 2018 USD ($)	Jul. 16, 2019 USD ($)
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Reverse share split			0.0636
Share consolidation basis nominal value per share \| $ / shares			$ 0.01571
Share consolidation basis, Renominalisation value per share \| $ / shares			$ 0.01
Net proceeds from issuance of stock after deducting underwriting discounts,commissions and offering cost	$ 2,400,000	$ 71,800,000				$ 3,037,000	$ 74,155,000	$ 74,200,000
Net losses				$ 31,271,000	$ 24,905,000	79,489,000	$ 52,799,000	77,056,000
Accumulated deficit				$ 211,282,000		$ 211,282,000		$ 131,793,000
Maximum
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Aggregate initial offering price of securities authorized to issue									$ 150,000,000
IPO
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Number of shares issued \| shares	200,000	6,150,000
Offering price per share \| $ / shares	$ 13.00	$ 13.00

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