Note 4 - Loans Receivable - Loans Receivable (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Loans receivable	$ 1,009,958	$ 1,174,728
Net deferred loan origination costs	(371)	(912)
Allowance for loan losses	(7,751)	(7,632)	$ (8,470)
Loans, net	1,002,578	1,168,008
Commercial Portfolio Segment [Member]
Loans receivable	405,057	418,343
Allowance for loan losses	(1,536)	(2,065)	(2,272)
Consumer Portfolio Segment [Member]
Loans receivable	1,812	2,211
Allowance for loan losses	(54)	(40)	(28)
One-to-Four Family Residential Real Estate [Member] \| Real Estate Portfolio [Member]
Loans receivable	41,691	55,750
Allowance for loan losses	(518)	(675)	(699)
Multi-family Mortgage [Member] \| Real Estate Portfolio [Member]
Loans receivable	452,241	563,750
Allowance for loan losses	(4,062)	(3,676)	(3,991)
Nonresidential Real Estate [Member] \| Real Estate Portfolio [Member]
Loans receivable	108,658	134,674
Allowance for loan losses	(1,569)	(1,176)	(1,476)
Construction and Land Loans [Member]
Loans receivable	499	0
Allowance for loan losses	$ (12)	$ 0	$ (4)

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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