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Note I - Income Taxes (Details Textual) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
Mar. 31, 2021 | Mar. 31, 2020 | Dec. 31, 2020 | Mar. 31, 2021 | Mar. 31, 2020 | Jun. 30, 2020
Effective Income Tax Rate Reconciliation, Percent, Total | 19.30% | 6.00% |  | 10.50% | 3.70% |
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent |  |  | 21.00% |  |  |
Effective Income Tax Rate Reconciliation, Global Intangible Low-taxed Income, Amount |  |  |  |  |  | $ (400)
Income Tax Benefit Cares Act |  |  |  | $ 300 |  |
Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Amount |  |  |  | 400 |  |
Income Tax Expense (Benefit), Continuing Operations, Adjustment of Deferred Tax (Asset) Liability |  |  |  | 500 |  |
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount | $ 0 |  |  | $ 0 |  |
Domestic Tax Authority [Member] |  |  |  |  |  |
Open Tax Year |  |  |  | 2017 2018 2019 2020 2021 |  |
State and Local Jurisdiction [Member] |  |  |  |  |  |
Open Tax Year |  |  |  | 2017 2018 2019 2020 2021 |  |
Foreign Tax Authority [Member] | Swiss Federal Tax Administration (FTA) [Member] |  |  |  |  |  |
Open Tax Year |  |  |  | 2019 2020 2021 |  |

X
- Definition Amount of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rates to pretax income (loss) from continuing operations, attributable to global intangible low-taxed income. + References No definition available. + Details
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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 the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to foreign income tax expense (benefit). + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -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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