Note 4 - Income Taxes (Details Textual) - USD ($)	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Effective Income Tax Rate Reconciliation, Percent, Total	16.90%	18.50%
Income Tax Expense (Benefit) Related to Recapitalization	$ (26,000)
Increase (Decrease) in Income Tax Expense from Non-deductible Recapitalization Expenses		$ 67,000
Increase (Decrease) in Income Tax Expense from Exercise of Options and Dividends Paid to Non-vested Shareholders		$ (87,000)

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(h)(2))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-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

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32698-109319

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