Note 5 - Loans and Allowance for Loan Losses - Loans by Category (Details) - USD ($)	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018	Dec. 31, 2017
Loans receivable	$ 768,965,653	$ 786,894,894
Allowance for loan losses	(7,846,622)	(7,995,569)	$ (7,103,000)	$ (7,107,000)
Deferred loan fees/costs, net	(573,387)	(600,719)
Net loans	760,545,644	778,298,606
Residential Portfolio Segment [Member] \| Real Estate Residential, One To Four Family Units [Member]
Loans receivable	127,332,191	132,410,810
Allowance for loan losses	(1,386,000)	(1,297,000)	(1,113,000)	(946,000)
Residential Portfolio Segment [Member] \| Real Estate Residential, Multi Family Units [Member]
Loans receivable	92,045,496	90,548,265
Allowance for loan losses	(694,000)	(641,000)	(487,000)	(464,000)
Real Estate, Construction [Member]
Loans receivable	89,605,230	88,553,995
Allowance for loan losses	(1,936,000)	(2,306,000)	(2,223,000)	(2,244,000)
Commercial Real Estate Portfolio Segment [Member]
Loans receivable	310,375,931	322,921,323
Allowance for loan losses	(2,137,000)	(2,093,000)
Commercial Portfolio Segment [Member]
Loans receivable	118,295,271	119,369,484
Allowance for loan losses	(974,000)	(1,160,000)	$ (958,000)	$ (1,031,000)
Consumer and Other Loans [Member]
Loans receivable	$ 31,311,534	$ 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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