Note 4 - Loans Receivable - Loans Receivable (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Loans receivable	$ 1,050,638	$ 1,009,958
Net deferred loan origination costs	284	371
Allowance for loan losses	(6,715)	(7,751)	$ (7,632)
Loans, net	1,044,207	1,002,578
Commercial Portfolio Segment [Member]
Loans receivable	489,512	405,057
Allowance for loan losses	(1,652)	(1,536)	(2,065)
Consumer Portfolio Segment [Member]
Loans receivable	1,685	1,812
Allowance for loan losses	(44)	(54)	(40)
One-to-Four Family Residential Real Estate [Member] \| Real Estate Portfolio [Member]
Loans receivable	30,133	41,691
Allowance for loan losses	(331)	(518)	(675)
Multi-family Mortgage [Member] \| Real Estate Portfolio [Member]
Loans receivable	426,136	452,241
Allowance for loan losses	(3,377)	(4,062)	(3,676)
Nonresidential Real Estate [Member] \| Real Estate Portfolio [Member]
Loans receivable	103,172	108,658
Allowance for loan losses	(1,311)	(1,569)	$ (1,176)
Construction and Land Loans [Member]
Loans receivable	0	499
Allowance for loan losses	$ 0	(12)
Construction and Land Loans [Member] \| Commercial Portfolio Segment [Member]
Loans receivable		$ 499

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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