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Note 13 - Stock-based Compensation (Details Textual) - USD ($)								1 Months Ended	3 Months Ended		9 Months Ended
	Feb. 07, 2023	Nov. 01, 2022	Feb. 02, 2022	Nov. 11, 2021	Aug. 16, 2021	Dec. 11, 2020	Dec. 01, 2020	Dec. 31, 2022	Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2023	Mar. 31, 2022	Jun. 30, 2022
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Number (in shares)									501,000	100,000	501,000	100,000
Share-Based Payment Arrangement, Expense									$ 607,818	$ 897,742	$ 2,206,239	$ 3,175,903
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term (Year)											1 year 9 months 7 days
Restricted Stock [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number (in shares)									429,376		429,376
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Number (in shares)									100,000		100,000
Share-Based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount									$ 3,952,212		$ 3,952,212
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)									6,667		6,667
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
The 2010 Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Number (in shares)									100,000		100,000		100,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period (in shares)									0		(0)
The 2010 Plan [Member] \| Restricted Stock [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number (in shares)									209,375		209,375
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		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		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)									113,500		113,500
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)	90,500			123,500				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] \| Four Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)			12,000								6,000