Note 5 - Loans and Allowance for Loan Losses - Loans by Category (Details) - USD ($)	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Loans receivable	$ 729,798,445	$ 728,914,025
Allowance for loan losses	(8,049,264)	(7,607,587)	$ (7,847,000)	$ (7,996,000)
Deferred loan fees/costs, net	(686,490)	(574,036)
Net loans	721,062,691	720,732,402
Residential Portfolio Segment [Member] \| Real Estate Residential, One To Four Family Units [Member]
Loans receivable	124,387,549	118,823,731
Allowance for loan losses	(1,154,000)	(1,001,000)	(1,386,000)	(1,297,000)
Residential Portfolio Segment [Member] \| Real Estate Residential, Multi Family Units [Member]
Loans receivable	82,548,977	87,448,418
Allowance for loan losses	(755,000)	(746,000)	(694,000)	(641,000)
Real Estate, Construction [Member]
Loans receivable	73,114,249	77,308,551
Allowance for loan losses	(1,629,000)	(1,749,000)	(1,936,000)	(2,306,000)
Commercial Real Estate Portfolio Segment [Member]
Loans receivable	300,704,999	300,619,387
Allowance for loan losses	(2,577,000)	(2,267,000)
Commercial Portfolio Segment [Member]
Loans receivable	118,181,468	114,047,753
Allowance for loan losses	(1,349,000)	(1,129,000)	$ (974,000)	$ (1,160,000)
Consumer and Other Loans [Member]
Loans receivable	$ 30,861,203	$ 30,666,185

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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