Note G - Income Taxes (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Federal, State and Local Income Tax Expense (Benefit), Gross, Continuing Operations	$ 600	$ 800
Operating Loss Carryforwards, Total	$ 1,300
Effective Income Tax Rate Reconciliation, Percent, Total	11.30%	5.40%
Effective Income Tax Rate, Continuing Operations, Excluding GILTI	18.90%
Undistributed Earnings of Foreign Subsidiaries	$ 0
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%	5.40%
Fiscal Years After June 30, 2021 [Member]
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%
Foreign Tax Authority [Member] | Swiss Federal Tax Administration (FTA) [Member]
Effective Income Tax Rate Reconciliation, Percent, Total	16.50%
Domestic Tax Authority [Member]
Open Tax Year	2017 2018 2019 2020 2021