Note 4 - Loans Receivable - Allowance for Loan Losses and Loans Receivable (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021	Mar. 31, 2021	Dec. 31, 2020
Allowance for loan losses, individually evaluated for impairment	$ 0	$ 30
Allowance for loan losses, collectively evaluated for impairment	6,786	6,685
Allowance for loan losses	6,786	6,715	$ 7,395	$ 7,751
Loan balances, individually evaluated for impairment	1,723	2,170
Loan balances, collectively evaluated for impairment	1,059,654	1,048,468
Loans receivable	1,061,377	1,050,638
Net deferred loan origination costs	478	284
Allowance for loan losses	(6,786)	(6,715)	(7,395)	(7,751)
Loans receivable, net of allowance for loan losses: March 31, 2022, $6,786 and December 31, 2021, $6,715	1,055,069	1,044,207
Real Estate Portfolio [Member] \| One-to-Four Family Residential Real Estate [Member]
Allowance for loan losses, individually evaluated for impairment	0	0
Allowance for loan losses, collectively evaluated for impairment	315	331
Allowance for loan losses	315	331	465	518
Loan balances, individually evaluated for impairment	1,067	1,299
Loan balances, collectively evaluated for impairment	27,154	28,834
Loans receivable	28,221	30,133
Allowance for loan losses	(315)	(331)	(465)	(518)
Real Estate Portfolio [Member] \| Multi-family Mortgage [Member]
Allowance for loan losses, individually evaluated for impairment	0	0
Allowance for loan losses, collectively evaluated for impairment	3,390	3,377
Allowance for loan losses	3,390	3,377	3,902	4,062
Loan balances, individually evaluated for impairment	492	498
Loan balances, collectively evaluated for impairment	435,030	425,638
Loans receivable	435,522	426,136
Allowance for loan losses	(3,390)	(3,377)	(3,902)	(4,062)
Real Estate Portfolio [Member] \| Nonresidential Real Estate [Member]
Allowance for loan losses, individually evaluated for impairment	0	30
Allowance for loan losses, collectively evaluated for impairment	957	1,281
Allowance for loan losses	957	1,311	1,592	1,569
Loan balances, individually evaluated for impairment	0	297
Loan balances, collectively evaluated for impairment	99,817	102,875
Loans receivable	99,817	103,172
Allowance for loan losses	(957)	(1,311)	(1,592)	(1,569)
Commercial Portfolio Segment [Member]
Allowance for loan losses, individually evaluated for impairment	0	0
Allowance for loan losses, collectively evaluated for impairment	2,078	1,652
Allowance for loan losses	2,078	1,652	1,377	1,536
Loan balances, individually evaluated for impairment	164	76
Loan balances, collectively evaluated for impairment	496,081	489,436
Loans receivable	496,245	489,512
Allowance for loan losses	(2,078)	(1,652)	(1,377)	(1,536)
Consumer Portfolio Segment [Member]
Allowance for loan losses, individually evaluated for impairment	0	0
Allowance for loan losses, collectively evaluated for impairment	46	44
Allowance for loan losses	46	44	47	54
Loan balances, individually evaluated for impairment	0	0
Loan balances, collectively evaluated for impairment	1,572	1,685
Loans receivable	1,572	1,685
Allowance for loan losses	$ (46)	$ (44)	$ (47)	$ (54)

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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The balance of financing receivables that were collectively evaluated for impairment.

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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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Amount of deferred fees paid by borrowers and unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of loans that are being amortized into income as an adjustment to yield. Excludes amounts for loans and leases covered under loss sharing agreements.

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