Note 10 - Employee Benefit Plans (Details Textual) - USD ($) $ in Thousands	12 Months Ended
Jun. 30, 2021	Jun. 30, 2020
Defined Contribution Plan, Employers Matching Contribution, Annual Vesting Percentage	100.00%
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent	4.00%
Defined Contribution Plan, Cost	$ 321	$ 282
Defined Benefit Plan, Accumulated Benefit Obligation	$ 3,140	$ 2,695
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate	3.00%	4.00%
Defined Benefit Plan, Other Cost (Credit)	$ 530	$ 305
Defined Benefit Plan, Plan Assets, Contributions by Employer	85	85
Restricted Stock [Member]
Share-based Payment Arrangement, Expense	168	$ 159
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total	$ 125
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)	3 years
Share-based Payment Arrangement, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	25.00%
Share-based Payment Arrangement, Tranche Three [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	25.00%
Share-based Payment Arrangement, Tranche Two, Three and Tour[Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)	3 years

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

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Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level.

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Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan.

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Amount of contribution received by defined benefit plan from employer which increases plan assets.

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Percentage of employer's matching contributions to a defined contribution plan that vests in a given year.

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Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Percentage of vesting of award under share-based payment arrangement.

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