Note 1 - Summary of Significant Accounting Policies (Details Textual) $ in Thousands	3 Months Ended
Jun. 30, 2018 USD ($)	Mar. 31, 2018 shares	Mar. 31, 2017 shares
Number of Reportable Segments		2
Weighted Average Number of Shares Outstanding, Basic, Total		4,711,608	4,672,316
Weighted Average Number Diluted Shares Outstanding Adjustment, Total		0	0
Accounting Standards Update 2018-02 [Member] \| Scenario, Forecast [Member]
Tax Cuts and Jobs Act, Reclassification from AOCI to Retained Earnings, Tax Effect \| $	$ 173

Amount of increase (decrease) in accumulated other comprehensive income (AOCI) for reclassification to retained earnings of tax effect from remeasurement of deferred tax pursuant to Tax Cuts and Jobs Act.

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

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- Definition

The sum of dilutive potential common shares or units used in the calculation of the diluted per-share or per-unit computation.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
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