Quarterly report pursuant to Section 13 or 15(d)

Note 11 - Stockholders' Equity (Details Textual)

Note 11 - Stockholders' Equity (Details Textual)			1 Months Ended		3 Months Ended			9 Months Ended		12 Months Ended
Note 11 - Stockholders' Equity (Details Textual)	May 23, 2024 shares	May 01, 2024 USD ($) $ / shares shares	Aug. 31, 2023 USD ($) $ / shares shares	Jul. 31, 2023 USD ($) $ / shares shares	Sep. 30, 2024 USD ($) shares	Jun. 30, 2024 USD ($) shares	Mar. 31, 2024 USD ($) shares	Sep. 30, 2024 USD ($) shares	Sep. 30, 2023 USD ($) shares	Dec. 31, 2019
Share-Based Payment Arrangement, Shares Withheld for Tax Withholding Obligation (in shares)								52,252	46,960
Share-Based Payment Arrangement, Decrease for Tax Withholding Obligation \| $								$ 552,000	$ 1,091,000
Stock Issued During Period, Shares, Issued for Services (in shares)								20,111
Stock Issued During Period, Shares, Employee Stock Purchase Plans (in shares)								3,444	9,635
Proceeds from Issuance of Common Stock \| $								$ 2,820,000	$ 3,788,000
Proceeds from Issuance Or Sale Of Equity, Net \| $								$ 7,306,000	$ 22,947,000
Stock Issued During Period, Shares, Issued for Class Action Settlement (in shares)									23,468
The 2019 Stock Incentive Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Additional Shares Authorized (in shares)	475,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized (in shares)	1,400,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares)					570,743			570,743
The 2019 Stock Incentive Plan [Member] \| Maximum [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period (Year)										10 years
May 2024 Public Offering Warrants [Member]
Stock Issued During Period, Shares, New Issues (in shares)		1,006,250
Shares Issued, Price Per Share (in dollars per share) \| $ / shares		$ 7.8
Class of Warrant or Right, Number of Securities Called by Each Warrant or Right (in shares)		1
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share) \| $ / shares		$ 0.2
Warrants and Rights Outstanding \| $		$ 3,100,000
May 2024 Warrants [Member]
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share) \| $ / shares		$ 7.8
Proceeds from Issuance of Warrants \| $		$ 3,000,000
May 2024 Warrants [Member] \| Underwriter [Member]
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share) \| $ / shares		$ 9.75
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)		39,125
Sale of Stock, Warrants, Commission Percent		2.00%
Proceeds from Issuance of Warrants \| $		$ 100,000
Warrants and Rights Outstanding, Term (Year)		5 years
Public Offering Warrant [Member]
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share) \| $ / shares				$ 27.5
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)				18,193
Sale of Stock, Warrants, Commission Percent				2.00%
Warrants and Rights Outstanding, Term (Year)				5 years
Yulho SPA Underwriter Warrant [Member]
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share) \| $ / shares			$ 25
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)			10,288
Warrants and Rights Outstanding, Term (Year)			5 years
ATM [Member]
Stock Issued During Period, Shares, New Issues (in shares)								306,049	162,215
Proceeds from Issuance of Common Stock \| $								$ 2,800,000	$ 3,800,000
May 2024 Public Offering [Member]
Proceeds from Issuance or Sale of Equity \| $		$ 7,300,000
Proceeds from Issuance Or Sale Of Equity, Net \| $		$ 4,200,000
July 2023 Public Offering [Member]
Stock Issued During Period, Shares, New Issues (in shares)				909,650
Proceeds from Issuance of Common Stock \| $				$ 18.3
Yulho Offering [Member]
Stock Issued During Period, Shares, New Issues (in shares)			227,273
Proceeds from Issuance of Common Stock \| $			$ 4,600,000
Restricted Stock Units (RSUs) [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)					20,111	6,250	5,576	57,126
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Fair Value \| $					$ 150,000	$ 40,000	$ 60,000
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period, Number of Installments						3	3
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)						3 years	3 years
Management and Employees [Member]
Stock Issued During Period, Shares, Restricted Stock Award, Gross (in shares)								129,857	70,694
Management and Employees [Member] \| Reissued Treasury Stock [Member]
Stock Issued During Period, Shares, Restricted Stock Award, Gross (in shares)								44,261	25,532
Board Members [Member]
Stock Issued During Period, Shares, Restricted Stock Award, Gross (in shares)								7,330	6,546
Stock Issued During Period, Shares, Issued for Services (in shares)									789
Board Members [Member] \| Restricted Stock Units (RSUs) [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)					18,582
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Fair Value \| $					$ 83,000
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period, Number of Installments					4
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)					9 months
Director [Member]
Stock Issued During Period, Shares, Issued for Services (in shares)								5,171	4,231
Former Employee [Member]
Stock Issued During Period, Shares, New Issues (in shares)								6,607
Employee [Member] \| Restricted Stock Units (RSUs) [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)					6,607
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Fair Value \| $					$ 28,000