Note 3 - Loans and Allowance for Loan Losses - Loans by Category (Details) - USD ($)	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Loans receivable	$ 637,375,018	$ 544,398,300
Allowance for loan losses	(7,107,418)	(5,742,449)	$ (5,812,000)	$ (6,589,000)
Deferred loan fees/costs, net	(662,591)	(382,211)
Net loans	629,605,009	538,273,640
Residential Portfolio Segment [Member] \| Real Estate Residential, One To Four Family Units [Member]
Loans receivable	106,300,790	106,410,559
Allowance for loan losses	(946,000)	(856,000)	(821,000)	(900,000)
Residential Portfolio Segment [Member] \| Real Estate Residential, Multi Family Units [Member]
Loans receivable	85,225,074	48,483,523
Allowance for loan losses	(464,000)	(206,000)	(177,000)	(127,000)
Real Estate, Construction [Member]
Loans receivable	64,743,582	40,912,307
Allowance for loan losses	(2,244,000)	(1,377,000)	(1,246,000)	(1,330,000)
Commercial Real Estate Portfolio Segment [Member]
Loans receivable	261,866,285	249,580,873
Allowance for loan losses	(1,789,000)	(1,687,000)	(1,526,000)	(1,992,000)
Commercial Portfolio Segment [Member]
Loans receivable	94,522,840	75,404,732
Allowance for loan losses	(1,031,000)	(1,168,000)	(1,382,000)	(1,954,000)
Consumer and Other Loans [Member]
Loans receivable	24,716,447	23,606,306
Allowance for loan losses	$ (454,000)	$ (337,000)	$ (223,000)	$ (185,000)

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
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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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