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Note 11 - Stock Based Compensation (Details Textual) - USD ($)									1 Months Ended	3 Months Ended
	Aug. 18, 2023	Feb. 07, 2023	Nov. 01, 2022	Feb. 02, 2022	Nov. 11, 2021	Aug. 16, 2021	Dec. 11, 2020	Dec. 01, 2020	Dec. 31, 2022	Sep. 30, 2023	Sep. 30, 2022	Jun. 30, 2023
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number (in shares)										436,183
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Number (in shares)										100,000
Share-Based Payment Arrangement, Expense										$ 739,783	$ 787,784
Share-Based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount										$ 2,666,958
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross (in shares)										0
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period (in shares)										0
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term (Year)										1 year 3 months 7 days
Restricted Stock [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number (in shares)										436.183
Restricted Stock [Member] \| Share-Based Payment Arrangement, Employee [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number (in shares)										3,334
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)						10,000
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)						3 years
Amended Equity Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Additional Shares Authorized (in shares)			600,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized (in shares)			2,600,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares)										193,500
The 2010 Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares)										462,567
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Number (in shares)										100,000		100,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross (in shares)										0
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period (in shares)										(0)
The 2010 Plan [Member] \| Restricted Stock [Member] \| Awards Granted February 7, 2023 [member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number (in shares)										90,500
The 2010 Plan [Member] \| Restricted Stock [Member] \| Two Employees [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number (in shares)										3,334
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)								20,000
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)							3 years
The 2010 Plan [Member] \| Restricted Stock [Member] \| Executives and Non-executive Directors [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number (in shares)										209,375
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)		90,500							209,375
Share-Based Compensation Arrangement by Share-Based Payment Award, Non-Option Equity Instruments, Forfeitures (in shares)									167,500
The 2010 Plan [Member] \| Restricted Stock [Member] \| Executives and Non-executive Directors [Member] \| Vesting Between April 2022 and January 2024 [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number (in shares)										113,500
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)					123,500
The 2010 Plan [Member] \| Restricted Stock [Member] \| Four Employees [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number (in shares)										6,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)				12,000
The 2010 Plan [Member] \| Restricted Stock [Member] \| Two Executives [Member] \| August 18, 2023 [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number (in shares)										10,140
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)	10,140
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)	3 years