Note 7 - Income Taxes (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2020
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount	$ 1,932	$ 2,575
Liability for Uncertainty in Income Taxes, Current		0
Income Tax Examination, Penalties and Interest Accrued, Total		0
Deferred Tax Assets Related to Net Operating Loss [Member]
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount	1,932	(2,575)
Capital Loss Carryforward [Member]
Tax Credit Carryforward, Amount		1,423
Capital Loss Carryforward [Member] | Tax Year 2025 [Member]
Tax Credit Carryforward, Amount		1,152
Capital Loss Carryforward [Member] | Tax Year 2026 [Member]
Tax Credit Carryforward, Amount		$ 271
Domestic Tax Authority [Member]
Operating Loss Carryforwards	22,210
State and Local Jurisdiction [Member]
Operating Loss Carryforwards	$ 4,407
State and Local Jurisdiction [Member] | New Jersey Division of Taxation [Member] | CII [Member]
Income Tax Examination, Year under Examination	2016		2016 2017 2018 2019