Note 4 - Loans Receivable - Activity in the Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024
Beginning Balance	$ 9,116	$ 8,142	$ 7,571	$ 8,345	$ 8,345
Provision for (recovery of) credit losses	(210)	472	1,790	435
Loans charged off	(102)	(743)	(582)	(936)
Recoveries	10	28	35	55
Ending balance	8,814	7,899	8,814	7,899	7,571
Commercial Portfolio Segment [Member]
Beginning Balance			1,146
Loans charged off			(259)		(5,867)
Recoveries			17		14
Ending balance	2,789		2,789		1,146
Consumer Portfolio Segment [Member]
Beginning Balance	44		48
Loans charged off			(26)		(44)
Recoveries			2		1
Ending balance	40		40		48
Home Equity and Junior Liens [Member] \| Real Estate Portfolio [Member]
Beginning Balance	47	61	54	75	75
Provision for (recovery of) credit losses	(2)	(5)	(9)	(19)
Loans charged off	0	0	0	0
Recoveries	0	0	0	0
Ending balance	45	56	45	56	54
One to Four Family First Liens [Member] \| Real Estate Portfolio [Member]
Beginning Balance	193	263	217	220	220
Provision for (recovery of) credit losses	(15)	(47)	(44)	(9)
Loans charged off	0	0	0	0
Recoveries	3	22	8	27
Ending balance	181	238	181	238	217
Multi Family Residential Real Estate, Senior Notes [Member] \| Real Estate Portfolio [Member]
Beginning Balance	4,295	4,402	4,320	4,178	4,178
Provision for (recovery of) credit losses	(99)	(54)	27	160
Loans charged off	0	0	(156)	0
Recoveries	3	6	8	16
Ending balance	4,199	4,354	4,199	4,354	4,320
Multi Family Residential Real Estate, Junior Notes [Member] \| Real Estate Portfolio [Member]
Beginning Balance	432	441	444	371	371
Provision for (recovery of) credit losses	(25)	10	104	80
Loans charged off	0	0	(141)	0
Recoveries	0	0	0	0
Ending balance	407	451	407	451	444
Owner Occupied Nonresidential Real Estate [Member] \| Real Estate Portfolio [Member]
Beginning Balance	181	173	180	144	144
Provision for (recovery of) credit losses	(12)	23	(11)	52
Loans charged off	0	0	0	0
Recoveries	0	0	0	0
Ending balance	169	196	169	196	180
Non-Owner Occupied Nonresidential Real Estate [Member] \| Real Estate Portfolio [Member]
Beginning Balance	1,052	1,224	1,162	1,022	1,022
Provision for (recovery of) credit losses	(68)	(5)	(178)	197
Loans charged off	0	0	0	0
Recoveries	0	0	0	0
Ending balance	984	1,219	984	1,219	1,162
Commercial Loans and Leases [Member] \| Real Estate Portfolio [Member]
Provision for (recovery of) credit losses	14		(117)
Loans charged off	(90)		(259)
Recoveries	4		17
Ending balance	585		585
Commercial Loans and Leases [Member] \| Commercial Portfolio Segment [Member]
Beginning Balance	657	1,267	944	1,964	1,964
Provision for (recovery of) credit losses		209		(332)
Loans charged off		(364)		(532)
Recoveries		0		12
Ending balance		1,112		1,112	944
Commercial Loans and Leases, Equipment Finance, Government [Member] \| Real Estate Portfolio [Member]
Provision for (recovery of) credit losses	(9)		2,038
Loans charged off	0		0
Recoveries	0		0
Ending balance	2,098		2,098
Commercial Loans and Leases, Equipment Finance, Government [Member] \| Commercial Portfolio Segment [Member]
Beginning Balance	2,107	97	60	148	148
Provision for (recovery of) credit losses		342		291
Loans charged off		(367)		(367)
Recoveries		0		0
Ending balance		72		72	60
Commercial Loans and Leases, Equipment Finance, Corporate Investment Grade [Member] \| Real Estate Portfolio [Member]
Provision for (recovery of) credit losses	(2)		(36)
Loans charged off	0		0
Recoveries	0		0
Ending balance	106		106
Commercial Loans and Leases, Equipment Finance, Corporate Investment Grade [Member] \| Commercial Portfolio Segment [Member]
Beginning Balance	108	160	142	191	191
Provision for (recovery of) credit losses		(15)		(46)
Loans charged off		0		0
Recoveries		0		0
Ending balance		145		145	142
Consumer [Member] \| Real Estate Portfolio [Member]
Beginning Balance		54		32	$ 32
Provision for (recovery of) credit losses	8	14	16	61
Loans charged off	(12)	(12)	(26)	(37)
Recoveries	0	0	2	0
Ending balance	$ 40	$ 56	$ 40	$ 56

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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+ 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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+ 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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+ 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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