Note 4 - Loans Receivable - Activity in the Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Beginning balance	$ 8,156	$ 7,824	$ 7,632	$ 8,470
Provision for (recovery of ) loan losses	(187)	(134)	326	3,736
Loans charged off	(16)	(104)	(51)	(4,663)
Recoveries	58	17	104	60
Total ending allowance balance	8,011	7,603	8,011	7,603
Real Estate Portfolio [Member]
Loans charged off	0		0
Commercial Portfolio Segment [Member]
Beginning balance	1,658	2,044	2,065	2,272
Provision for (recovery of ) loan losses	(178)	(8)	(588)	4,203
Loans charged off	0	0	0	(4,443)
Recoveries	0	4	3	8
Total ending allowance balance	1,480	2,040	1,480	2,040
Consumer Portfolio Segment [Member]
Beginning balance	46	31	40	28
Provision for (recovery of ) loan losses	16	10	52	28
Loans charged off	(14)	(5)	(44)	(20)
Recoveries	0	0	0	0
Total ending allowance balance	48	36	48	36
Construction and Land Loans [Member]
Beginning balance		3		4
Provision for (recovery of ) loan losses		(1)		(2)
Loans charged off		0		0
Recoveries		0		0
Total ending allowance balance		2		2
One-to-Four Family Residential Real Estate [Member] \| Real Estate Portfolio [Member]
Beginning balance	665	563	675	699
Provision for (recovery of ) loan losses	(42)	56	(63)	(30)
Loans charged off	(2)	(44)	(7)	(117)
Recoveries	2	5	18	28
Total ending allowance balance	623	580	623	580
Multi-family Mortgage [Member] \| Real Estate Portfolio [Member]
Beginning balance	4,185	3,988	3,676	3,991
Provision for (recovery of ) loan losses	(98)	(268)	384	(287)
Loans charged off	0	0	0	0
Recoveries	56	8	83	24
Total ending allowance balance	4,143	3,728	4,143	3,728
Nonresidential Real Estate [Member] \| Real Estate Portfolio [Member]
Beginning balance	1,602	1,195	1,176	1,476
Provision for (recovery of ) loan losses	115	77	541	(176)
Loans charged off		(55)		(83)
Recoveries	0	0	0	0
Total ending allowance balance	$ 1,717	$ 1,217	$ 1,717	$ 1,217

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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