Note 17 - New Accounting Pronouncements (Details Textual) - USD ($)	12 Months Ended
Dec. 31, 2017	Jan. 01, 2019
Reclassifications of Amounts Within AOCI to Retained Earnings Due to Tax Reform	$ 31,818
Accounting Standards Update 2016-02 [Member] \| Minimum [Member] \| Scenario, Forecast [Member]
Operating Lease, Right-of-Use Asset		$ 10,000,000
Operating Lease, Liability, Total		10,000,000
Accounting Standards Update 2016-02 [Member] \| Maximum [Member] \| Scenario, Forecast [Member]
Operating Lease, Right-of-Use Asset		11,000,000
Operating Lease, Liability, Total		$ 11,000,000
Accounting Standards Update 2018-02 [Member] \| New Accounting Pronouncement, Early Adoption, Effect [Member]
Reclassifications of Amounts Within AOCI to Retained Earnings Due to Tax Reform	$ 31,818

Represents the amounts within accumulated other comprehensive income reclassified to retained earnings during the period as a result of tax reform.

No definition available.

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977

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- Definition

Amount of lessee's right to use underlying asset under operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (a)
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