Note 4 - Loans and Allowance for Loan Losses - Loans by Category (Details) - USD ($)	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Loans receivable	$ 786,894,894	$ 637,375,018
Allowance for loan losses	(7,995,569)	(7,107,418)	$ (5,742,000)	$ (5,812,000)
Deferred loan fees/costs, net	(600,719)	(662,591)
Net loans	778,298,606	629,605,009
Residential Portfolio Segment [Member] \| Real Estate Residential, One To Four Family Units [Member]
Loans receivable	132,410,810	106,300,790
Allowance for loan losses	(1,297,000)	(946,000)	(856,000)	(821,000)
Residential Portfolio Segment [Member] \| Real Estate Residential, Multi Family Units [Member]
Loans receivable	90,548,265	85,225,074
Allowance for loan losses	(641,000)	(464,000)	(206,000)	(177,000)
Real Estate, Construction [Member]
Loans receivable	88,553,995	64,743,582
Allowance for loan losses	(2,306,000)	(2,244,000)	(1,377,000)	(1,246,000)
Commercial Real Estate Portfolio Segment [Member]
Loans receivable	322,921,323	261,866,285
Allowance for loan losses	(2,093,000)	(1,789,000)	(1,687,000)	(1,526,000)
Commercial Portfolio Segment [Member]
Loans receivable	119,369,484	94,522,840
Allowance for loan losses	(1,160,000)	(1,031,000)	$ (1,168,000)	$ (1,382,000)
Consumer and Other Loans [Member]
Loans receivable	$ 33,091,017	$ 24,716,447

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.

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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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