Note 2 - Investments - Realized Gains and Losses Related to the Sale of Securities (Details) - USD ($)	3 Months Ended	12 Months Ended
Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016	Dec. 31, 2015
Gross gains	$ 192,405	$ 10,838	$ 122,192	$ 90,602
Gross losses			(21,814)	(92,126)
Net security (losses) gains	$ 192,405	$ 10,838	$ 100,378	$ (1,524)

The net gain (loss) realized from the sale, exchange, redemption, or retirement of securities, not separately or otherwise categorized as trading, available-for-sale, or held-to-maturity.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.13(h))
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04.3)
-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

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