Note 6 - Income Taxes (Details Textual) - USD ($)	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Income Tax Expense (Benefit), Total	$ 225,000
Effective Income Tax Rate Reconciliation, Percent, Total	(36.80%)	7.10%
Foreign Tax Authority [Member] \| Tax Year 2004 [Member]
Income Tax Examination, Liability (Refund) Adjustment from Settlement with Taxing Authority			$ 84,000

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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

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