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)

v3.19.1

Basis of Presentation - Additional Information (Details) $ / shares in Units, $ in Thousands				3 Months Ended		12 Months Ended
	Jun. 26, 2018 USD ($) $ / shares shares	May 30, 2018 USD ($) $ / shares shares	May 15, 2018 $ / shares	Mar. 31, 2019 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2018 USD ($)	Oct. 31, 2019 USD ($)
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	$ 71,800		$ 74,200
Net losses				20,580	$ 12,146	$ 77,056
Accumulated deficit				152,373		131,793
Cash and cash equivalents				64,603		44,551
Short-term investments				4,997		$ 40,000
Cash resources available under the secured credit facility				$ 15,000
Scenario, Forecast
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Cash resources available under the secured credit facility							$ 15,000
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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