Note 8 - Income Taxes (Details Textual) - USD ($)	9 Months Ended	12 Months Ended
Dec. 31, 2017	Dec. 31, 2018
Income Tax Expense (Benefit), Continuing Operations, Adjustment of Deferred Tax (Asset) Liability	$ 206,693
Effective Income Tax Rate Reconciliation, Percent	32.00%
Unrecognized Tax Benefits	$ 0
Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Amount of Unrecorded Benefit	0
Unrecognized Tax Benefits, Interest on Income Taxes Accrued	$ 0
Open Tax Year	1999
Earliest Tax Year [Member]
Open Tax Year	2013
Latest Tax Year [Member]
Open Tax Year	2016
Scenario, Forecast [Member]
Effective Income Tax Rate Reconciliation, Percent		29.00%

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/presentationRef
-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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-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

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Amount of income tax expense (benefit) from continuing operations attributable to an adjustment of a deferred tax liability or asset for enacted changes in tax laws or rates or a change in the tax status of the entity.

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Tax year that remains open to examination under enacted tax laws, in CCYY format.

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Amount of unrecognized tax benefits.

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Amount of interest expense accrued for an underpayment of income taxes.

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