v3.20.2

Note 9 - Stockholders' Equity (Details Textual) - USD ($)					3 Months Ended				9 Months Ended
	Jul. 23, 2020	Jun. 16, 2020	May 09, 2019	Jun. 21, 2016	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Proceeds from Issuance of Common Stock									$ 11,400,000	$ 1,233,000
Stock Issued During Period, Value, New Issues					$ 9,951,000	$ 665,000	$ 784,000	$ 1,233,000
The 2020 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares)		5,500,000
The 2020 Equity Incentive Plan [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares to be Added (in shares)		14,892,170
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period (Year)		10 years
Employee Stock Purchase Plan (ESPP) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares)		4,900,000
Private Placement [Member] | Armistice Capital and Rock Springs Capital [Member]
Stock Issued During Period, Shares, New Issues (in shares)	9,433,962
Shares Issued, Price Per Share (in dollars per share)	$ 1.06
Proceeds from Issuance of Common Stock	$ 10,000,000.0
Estimated Offering Costs	$ 49,000
ATM Agreement [Member]
Stock Issued During Period, Shares, New Issues (in shares)					0				876,800
Proceeds from Issuance Initial Public Offering			$ 80,000,000.0	$ 40,000,000.0
Aggregate Offering Price, Increase During Period			$ 40,000,000.0
Stock Issued During Period, Value, New Issues									$ 1,500,000
Aggregate Offering Price, Maximum									$ 43,800,000

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