Note 4 - Loans, Allowance for Credit Losses and Credit Quality - Schedule of Allowance for Credit Losses (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024	Dec. 31, 2024
Balance	$ 8,808	$ 8,670	$ 8,884	$ 8,591	$ 8,591
Charge-offs	(2)	(3)	(84)	(3)
Recoveries	1	0	1	0
(Benefit) provision	1,079	358	1,085	437
Real Estate Portfolio Segment [Member] \| One-to-four Family Residential Loan [Member]
Balance	2,698	3,511	2,928	3,555	3,555
Charge-offs	0	0	0	0	0
Recoveries	0	0	0	0
(Benefit) provision	135	93	(95)	49
Real Estate Portfolio Segment [Member] \| Multifamily Loan [Member]
Balance	2,632	1,283	2,422	1,190	1,190
Charge-offs	0	0	0	0	0
Recoveries	0	0	0	0
(Benefit) provision	134	21	344	114
Real Estate Portfolio Segment [Member] \| Commercial Loan [Member]
Balance	2,532	1,672	2,260	1,636	1,636
Charge-offs	0	0	0	0	0
Recoveries	0	0	0	0
(Benefit) provision	586	68	858	104
Real Estate Portfolio Segment [Member] \| Home Equity Loan [Member]
Balance	119	319	118	321	321
Charge-offs	0	0	0	0	0
Recoveries	0	0	0	0
(Benefit) provision	15	44	16	42
Real Estate Portfolio Segment [Member] \| Construction Loans [Member]
Balance	708	1,681	1,036	1,757	1,757
Charge-offs	0	0	0	0	0
Recoveries	0	0	0	0
(Benefit) provision	208	133	(120)	57
Other Portfolio Segment [Member] \| Commercial Loan [Member]
Balance	118	203	119	131	131
Charge-offs	0	0	(81)	0	0
Recoveries	0	0	0	0
(Benefit) provision	(5)	(4)	75	68
Other Portfolio Segment [Member] \| Consumer Loan [Member]
Balance	1	1	1	1	1
Charge-offs	(2)	(3)	(3)	(3)	$ (4)
Recoveries	1	0	1	0
(Benefit) provision	$ 6	$ 3	$ 7	$ 3

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479344/326-20-45-1

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- Definition

Amount, excluding accrued interest, of increase in allowance for credit loss on financing receivable from recovery. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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- Definition

Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from writeoff. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-6

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- Definition

Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147476148/220-40-50-22

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