Note 4 - Loans and Allowance for Loan Losses - Loans by Category (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Loans receivable	$ 728,914,025	$ 786,894,894
Allowance for loan losses	(7,607,587)	(7,995,569)	$ (7,107,000)	$ (5,742,000)
Deferred loan fees/costs, net	(574,036)	(600,719)
Net loans	720,732,402	778,298,606
Residential Portfolio Segment [Member] \| Real Estate Residential, One To Four Family Units [Member]
Loans receivable	118,823,731	132,410,810
Allowance for loan losses	(1,001,000)	(1,297,000)	(946,000)	(856,000)
Residential Portfolio Segment [Member] \| Real Estate Residential, Multi Family Units [Member]
Loans receivable	87,448,418	90,548,265
Allowance for loan losses	(746,000)	(641,000)	(464,000)	(206,000)
Real Estate, Construction [Member]
Loans receivable	77,308,551	88,553,995
Allowance for loan losses	(1,749,000)	(2,306,000)	(2,244,000)	(1,377,000)
Commercial Real Estate Portfolio Segment [Member]
Loans receivable	300,619,387	322,921,323
Allowance for loan losses	(2,267,000)	(2,093,000)	(1,789,000)
Commercial Portfolio Segment [Member]
Loans receivable	114,047,753	119,369,484
Allowance for loan losses	(1,129,000)	(1,160,000)	$ (1,031,000)	$ (1,168,000)
Consumer and Other Loans [Member]
Loans receivable	$ 30,666,185	$ 33,091,017

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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