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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Note 5 - Loans and Allowance for Loan Losses - Loans by Category (Details) - USD ($)	Sep. 30, 2020	Jun. 30, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Dec. 31, 2018
Loans receivable	$ 783,278,283		$ 728,914,025
Allowance for loan losses	(9,680,688)	$ (8,788,000)	(7,607,587)	$ (7,557,000)	$ (7,671,000)	$ (7,996,000)
Deferred loan fees/costs, net	(2,150,075)		(574,036)
Net loans	771,447,520		720,732,402
Residential Portfolio Segment [Member] \| Real Estate Residential, One To Four Family Units [Member]
Loans receivable	128,467,837		118,823,731
Allowance for loan losses	(1,509,000)	(1,539,000)	(1,001,000)	(991,000)	(948,000)	(1,297,000)
Residential Portfolio Segment [Member] \| Real Estate Residential, Multi Family Units [Member]
Loans receivable	89,762,581		87,448,418
Allowance for loan losses	(920,000)	(794,000)	(746,000)	(723,000)	(673,000)	(641,000)
Real Estate, Construction [Member]
Loans receivable	69,915,937		77,308,551
Allowance for loan losses	(1,622,000)	(1,569,000)	(1,749,000)	(1,952,000)	(2,169,000)	(2,306,000)
Commercial Real Estate Portfolio Segment [Member]
Loans receivable	304,555,366		300,619,387
Allowance for loan losses	(3,269,000)	(2,998,000)		(2,309,000)	(2,188,000)
Commercial Portfolio Segment [Member]
Loans receivable	163,097,935		114,047,753
Allowance for loan losses	(1,443,000)	$ (1,299,000)	(1,129,000)	$ (1,060,000)	$ (1,236,000)	$ (1,160,000)
Consumer and Other Loans [Member]
Loans receivable	$ 27,478,627		$ 30,666,185