Note 4 - Loans Receivable - Activity in the Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Beginning balance	$ 7,751	$ 7,632
Provision for (recovery of ) loan losses	(335)	471
Loans charged off	(95)	(18)
Recoveries	74	27
Total ending allowance balance	7,395	8,112
Commercial Portfolio Segment [Member]
Beginning balance	1,536	2,065
Provision for (recovery of ) loan losses	(74)	(12)
Loans charged off	(86)	0
Recoveries	1	2
Total ending allowance balance	1,377	2,055
Consumer Portfolio Segment [Member]
Beginning balance	54	40
Provision for (recovery of ) loan losses	0	19
Loans charged off	(9)	(13)
Recoveries	2	0
Total ending allowance balance	47	46
One-to-Four Family Residential Real Estate [Member] \| Real Estate Portfolio [Member]
Beginning balance	518	675
Provision for (recovery of ) loan losses	(113)	(1)
Loans charged off	0	(5)
Recoveries	60	13
Total ending allowance balance	465	682
Multi-family Mortgage [Member] \| Real Estate Portfolio [Member]
Beginning balance	4,062	3,676
Provision for (recovery of ) loan losses	(171)	181
Loans charged off	0	0
Recoveries	11	12
Total ending allowance balance	3,902	3,869
Nonresidential Real Estate [Member] \| Real Estate Portfolio [Member]
Beginning balance	1,569	1,176
Provision for (recovery of ) loan losses	23	284
Loans charged off	0	0
Recoveries	0	0
Total ending allowance balance	1,592	$ 1,460
Construction and Land Loans [Member]
Beginning balance	12
Provision for (recovery of ) loan losses	0
Loans charged off	0
Recoveries	0
Total ending allowance balance	$ 12

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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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 of expense related to estimated loss from loan and lease transactions.

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