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, 2019	Jun. 30, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Dec. 31, 2017
Loans receivable	$ 752,225,370		$ 786,894,894
Allowance for loan losses	(7,557,311)	$ (7,671,000)	(7,995,569)	$ (7,732,000)	$ (7,573,000)	$ (7,107,000)
Deferred loan fees/costs, net	(645,203)		(600,719)
Net loans	744,022,856		778,298,606
Residential Portfolio Segment [Member] \| Real Estate Residential, One To Four Family Units [Member]
Loans receivable	121,690,131		132,410,810
Allowance for loan losses	(991,000)	(948,000)	(1,297,000)	(1,331,000)	(1,237,000)	(946,000)
Residential Portfolio Segment [Member] \| Real Estate Residential, Multi Family Units [Member]
Loans receivable	93,628,789		90,548,265
Allowance for loan losses	(723,000)	(673,000)	(641,000)	(650,000)	(553,000)	(464,000)
Real Estate, Construction [Member]
Loans receivable	88,175,253		88,553,995
Allowance for loan losses	(1,952,000)	(2,169,000)	(2,306,000)	(2,301,000)	(2,484,000)	(2,244,000)
Commercial Real Estate Portfolio Segment [Member]
Loans receivable	308,270,953		322,921,323
Allowance for loan losses	(2,309,000)	(2,188,000)		(1,945,000)	(1,787,000)
Commercial Portfolio Segment [Member]
Loans receivable	108,738,413		119,369,484
Allowance for loan losses	(1,060,000)	$ (1,236,000)	(1,160,000)	$ (1,031,000)	$ (1,085,000)	$ (1,031,000)
Consumer and Other Loans [Member]
Loans receivable	$ 31,721,831		$ 33,091,017