Note 4 - Loans and Allowance for Loan Losses - Loans by Category (Details) - USD ($)	Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020	Dec. 31, 2019
Loans receivable	$ 755,152,828	$ 753,408,413
Allowance for loan losses	(9,887,939)	(9,617,024)	$ (8,049,000)	$ (7,608,000)
Deferred loan fees/costs, net	(2,044,113)	(1,642,118)
Net loans	743,220,776	742,149,271
Residential Portfolio Segment [Member] \| Real Estate Residential, One To Four Family Units [Member]
Loans receivable	114,706,270	115,799,200
Allowance for loan losses	(1,426,000)	(1,445,000)	(1,154,000)	(1,001,000)
Residential Portfolio Segment [Member] \| Real Estate Residential, Multi Family Units [Member]
Loans receivable	88,353,385	90,028,775
Allowance for loan losses	(998,000)	(1,058,000)	(755,000)	(746,000)
Real Estate, Construction [Member]
Loans receivable	85,711,951	70,847,330
Allowance for loan losses	(1,374,000)	(1,132,000)	(1,629,000)	(1,749,000)
Commercial Real Estate Portfolio Segment [Member]
Loans receivable	308,660,565	305,673,212
Allowance for loan losses	(3,831,000)	(3,624,000)	(2,577,000)	(2,267,000)
Commercial Portfolio Segment [Member]
Loans receivable	133,076,722	144,326,350
Allowance for loan losses	(1,257,000)	(1,129,000)	$ (1,349,000)	$ (1,129,000)
Consumer and Other Loans [Member]
Loans receivable	$ 24,643,935	$ 26,733,546

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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