Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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Note 10 - Stock-based Compensation (Details Textual) - USD ($)						1 Months Ended		3 Months Ended		9 Months Ended
	Dec. 11, 2020	Dec. 01, 2020	Jan. 09, 2020	Jan. 06, 2020	Nov. 04, 2017	Dec. 31, 2020	Nov. 30, 2019	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2021	Mar. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Nov. 13, 2019
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number, Ending Balance (in shares)	300,000							100,000		100,000		100,000	100,000
Share-based Payment Arrangement, Expense								$ 983,988	$ 862,125	$ 2,886,046	$ 2,485,448
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term (Year)										3 years 281 days
Share-based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount								$ 284,839		$ 284,839
President and CEO [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in shares)				100,000
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price (in dollars per share)				$ 14.50
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number, Ending Balance (in shares)								401,333		401,333
The 2010 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized (in shares)					500,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares)														2,000,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number, Ending Balance (in shares)								100,000		100,000			100,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total								$ 4,349,404		$ 4,349,404
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in shares)
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price (in dollars per share)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period (in shares)								0		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, Ending Balance (in shares)						205,833
The 2010 Plan [Member] \| Restricted Stock [Member] \| Two Executives and Non-executive Directors [Member] \| November 2019 Grant [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number, Ending Balance (in shares)								158,000		158,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)							158,000
The 2010 Plan [Member] \| Restricted Stock [Member] \| President and Chief Executive Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number, Ending Balance (in shares)								37,500		37,500
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)			75,000
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)			2 years
The 2010 Plan [Member] \| Restricted Stock [Member] \| Two Employees [Member]
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, Grants in Period (in shares)	162,500
The 2010 Plan [Member] \| Restricted Stock [Member] \| Chief Executive Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)	23,333					23,333