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Note I - Income Taxes (Details Textual) - USD ($) | 3 Months Ended | 9 Months Ended
--- | --- | ---
Mar. 31, 2020 | Mar. 31, 2019 | Mar. 31, 2020 | Mar. 31, 2019
Effective Income Tax Rate Reconciliation, Percent, Total | 6.00% | 18.90% | 3.70% | 20.10%
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent |  |  | 21.00% |
Income Tax Expense (Benefit), Continuing Operations, Discrete Tax Items Due to Tax Act, Amount, Total | $ 74,000 |  | $ 64,000 |
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount | $ 0 |  | $ 0 |
Domestic Tax Authority [Member] |  |  |  |
Open Tax Year |  |  | 2017 2018 2019 2020 |
State and Local Jurisdiction [Member] |  |  |  |
Open Tax Year |  |  | 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 |
Foreign Tax Authority [Member] | Swiss Federal Tax Administration (FTA) [Member] |  |  |  |
Open Tax Year |  |  | 2018 2019 2020 |

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- Definition Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319 + Details
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- Definition Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32537-109319 + Details
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