Note 4 - Loans and Allowance for Loan Losses - Loans by Category (Details) - USD ($)	Sep. 30, 2017	Jun. 30, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Dec. 31, 2015
Loans receivable	$ 624,592,058		$ 544,398,300
Allowance for loan losses	(7,009,097)	$ (6,640,000)	(5,742,449)	$ (6,397,000)	$ (6,181,000)	$ (5,812,000)
Deferred loan fees/costs, net	(698,909)		(382,211)
Net loans	616,884,052		538,273,640
Residential Portfolio Segment [Member] \| Real Estate Residential, One To Four Family Units [Member]
Loans receivable	107,750,990		106,410,559
Allowance for loan losses	(856,000)	(936,000)	(856,000)	(885,000)	(862,000)	(821,000)
Residential Portfolio Segment [Member] \| Real Estate Residential, Multi Family Units [Member]
Loans receivable	74,653,469		48,483,523
Allowance for loan losses	(375,000)	(323,000)	(206,000)	(163,000)	(157,000)	(177,000)
Real Estate, Construction [Member]
Loans receivable	62,046,871		40,912,307
Allowance for loan losses	(2,279,000)	(1,739,000)	(1,377,000)	(1,996,000)	(1,668,000)	(1,246,000)
Commercial Real Estate Portfolio Segment [Member]
Loans receivable	266,292,510		249,580,873
Allowance for loan losses	(1,767,000)	(1,954,000)	(1,687,000)	(1,699,000)	(1,613,000)	(1,526,000)
Commercial Portfolio Segment [Member]
Loans receivable	90,186,600		75,404,732
Allowance for loan losses	(1,134,000)	(1,226,000)	(1,168,000)	(1,323,000)	(1,366,000)	(1,382,000)
Consumer and Other Loans [Member]
Loans receivable	23,661,618		23,606,306
Allowance for loan losses	$ (427,000)	$ (335,000)	$ (337,000)	$ (277,000)	$ (288,000)	$ (223,000)

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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-Section 50
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-Subparagraph (g)
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Subparagraph (SX 210.9-03.7(d))
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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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Amount of deferred fees paid by borrowers and unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of loans that are being amortized into income as an adjustment to yield. Excludes amounts for loans and leases covered under loss sharing agreements.

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