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Note 4 - Loans Receivable - Risk Categories of Loans By Class of Loans (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2024	Dec. 31, 2023
Loans receivable	$ 995,887	$ 1,059,106
Real Estate Portfolio [Member] | One-to-Four Family Residential Real Estate [Member]
Loans receivable	17,707	18,945
Financing Receivable, current year	0	489
Financing Receivable, one year before	487	0
Financing Receivable, two years before	0	0
Financing Receivable, three years before	0	130
Financing Receivable, four years before	90	0
Financing Receivable, prior	13,491	14,356
Financing Receivable, revolving	3,639	3,970
Current period recoveries, current year	0	0
Current period recoveries, one year before	0	0
Current period recoveries, two years before	0	0
Current period recoveries, three years before	0	0
Current period recoveries, four years before	0	0
Current period recoveries, prior	5	45
Current period recoveries, revolving	0	0
Current period recoveries, total	5	45
Current period gross charge-offs		0
Current period gross charge-offs		0
Current period gross charge-offs		0
Current period gross charge-offs		0
Current period gross charge-offs		0
Current period gross charge-offs		(1)
Current period gross charge-offs		0
Current period gross charge-offs		(1)
Recoveries (charge-offs), net, current year		0
Recoveries (charge-offs), net, one year before		0
Recoveries (charge-offs), net, two years before		0
Recoveries (charge-offs), net, three years before		0
Recoveries (charge-offs), net, four years before		0
Recoveries (charge-offs), net, prior		44
Recoveries (charge-offs), net, revolving		0
Recoveries (charge-offs), net, total		44
Real Estate Portfolio [Member] | Multi-family Mortgage [Member]
Loans receivable	527,542	527,460
Financing Receivable, current year	20,299	43,504
Financing Receivable, one year before	38,262	212,740
Financing Receivable, two years before	209,926	112,667
Financing Receivable, three years before	111,048	57,743
Financing Receivable, four years before	55,479	22,064
Financing Receivable, prior	85,471	70,007
Financing Receivable, revolving	7,057	8,735
Current period recoveries, current year	0	0
Current period recoveries, one year before	0	0
Current period recoveries, two years before	0	0
Current period recoveries, three years before	0	0
Current period recoveries, four years before	0	0
Current period recoveries, prior	10	20
Current period recoveries, revolving	0	0
Current period recoveries, total	10	20
Real Estate Portfolio [Member] | Nonresidential Real Estate [Member]
Loans receivable	109,635	118,016
Financing Receivable, current year	13,540	17,618
Financing Receivable, one year before	15,389	53,256
Financing Receivable, two years before	48,762	21,939
Financing Receivable, three years before	15,212	7,787
Financing Receivable, four years before	7,557	9,024
Financing Receivable, prior	9,038	8,288
Financing Receivable, revolving	137	104
Commercial Portfolio Segment [Member]
Loans receivable	339,216	393,321
Financing Receivable, current year	12,891	50,026
Financing Receivable, one year before	41,682	158,485
Financing Receivable, two years before	124,882	63,552
Financing Receivable, three years before	48,538	33,581
Financing Receivable, four years before	24,478	3,028
Financing Receivable, prior	1,850	1,379
Financing Receivable, revolving	84,895	83,270
Current period recoveries, current year	0	0
Current period recoveries, one year before	0	0
Current period recoveries, two years before	0	37
Current period recoveries, three years before	5	40
Current period recoveries, four years before	7	0
Current period recoveries, prior	0	0
Current period recoveries, revolving	0	0
Current period recoveries, total	12	77
Current period gross charge-offs	0	(20)
Current period gross charge-offs	(4)	(1,850)
Current period gross charge-offs	(116)	0
Current period gross charge-offs	(43)	(306)
Current period gross charge-offs	(5)	0
Current period gross charge-offs	0	0
Current period gross charge-offs	0	0
Current period gross charge-offs	(168)	(2,176)
Recoveries (charge-offs), net, current year	0	(20)
Recoveries (charge-offs), net, one year before	(4)	(1,850)
Recoveries (charge-offs), net, two years before	(116)	37
Recoveries (charge-offs), net, three years before	(38)	(266)
Recoveries (charge-offs), net, four years before	2	0
Recoveries (charge-offs), net, prior	0	0
Recoveries (charge-offs), net, revolving	0	0
Recoveries (charge-offs), net, total	(156)	(2,099)
Consumer Portfolio Segment [Member]
Loans receivable	1,787	1,364
Financing Receivable, current year	726	336
Financing Receivable, one year before	208	8
Financing Receivable, two years before	7	140
Financing Receivable, three years before	55	80
Financing Receivable, four years before	50	247
Financing Receivable, prior	98	0
Financing Receivable, revolving	643	553
Current period recoveries, current year		0
Current period recoveries, one year before		0
Current period recoveries, two years before		0
Current period recoveries, three years before		0
Current period recoveries, four years before		0
Current period recoveries, prior		0
Current period recoveries, revolving		1
Current period recoveries, total		1
Current period gross charge-offs	0	0
Current period gross charge-offs	0	0
Current period gross charge-offs	0	0
Current period gross charge-offs	0	0
Current period gross charge-offs	0	0
Current period gross charge-offs	0	0
Current period gross charge-offs	(25)	(52)
Current period gross charge-offs	(25)	(52)
Recoveries (charge-offs), net, current year		0
Recoveries (charge-offs), net, one year before		0
Recoveries (charge-offs), net, two years before		0
Recoveries (charge-offs), net, three years before		0
Recoveries (charge-offs), net, four years before		0
Recoveries (charge-offs), net, prior		0
Recoveries (charge-offs), net, revolving		(51)
Recoveries (charge-offs), net, total		(51)
Pass [Member]
Loans receivable	938,445	993,157
Pass [Member] | Real Estate Portfolio [Member] | One-to-Four Family Residential Real Estate [Member]
Loans receivable	17,434	18,492
Financing Receivable, current year	0	489
Financing Receivable, one year before	487	0
Financing Receivable, two years before	0	0
Financing Receivable, three years before	0	130
Financing Receivable, four years before	90	0
Financing Receivable, prior	13,375	14,069
Financing Receivable, revolving	3,482	3,804
Pass [Member] | Real Estate Portfolio [Member] | Multi-family Mortgage [Member]
Loans receivable	522,856	518,538
Financing Receivable, current year	20,299	43,386
Financing Receivable, one year before	38,046	210,878
Financing Receivable, two years before	208,081	108,563
Financing Receivable, three years before	111,048	57,480
Financing Receivable, four years before	55,219	22,064
Financing Receivable, prior	83,106	67,432
Financing Receivable, revolving	7,057	8,735
Pass [Member] | Real Estate Portfolio [Member] | Nonresidential Real Estate [Member]
Loans receivable	105,106	114,155
Financing Receivable, current year	13,083	17,618
Financing Receivable, one year before	15,389	50,898
Financing Receivable, two years before	46,104	20,436
Financing Receivable, three years before	13,798	7,787
Financing Receivable, four years before	7,557	9,024
Financing Receivable, prior	9,038	8,288
Financing Receivable, revolving	137	104
Pass [Member] | Commercial Portfolio Segment [Member]
Loans receivable	291,274	340,623
Financing Receivable, current year	12,891	43,972
Financing Receivable, one year before	35,621	130,444
Financing Receivable, two years before	98,669	62,280
Financing Receivable, three years before	47,820	32,633
Financing Receivable, four years before	23,821	3,028
Financing Receivable, prior	1,850	1,379
Financing Receivable, revolving	70,602	66,887
Pass [Member] | Consumer Portfolio Segment [Member]
Loans receivable	1,775	1,349
Financing Receivable, current year	726	336
Financing Receivable, one year before	208	8
Financing Receivable, two years before	7	140
Financing Receivable, three years before	55	80
Financing Receivable, four years before	50	247
Financing Receivable, prior	98	0
Financing Receivable, revolving	631	538
Watch [Member]
Loans receivable	19,630	28,362
Watch [Member] | Real Estate Portfolio [Member] | One-to-Four Family Residential Real Estate [Member]
Loans receivable	67	144
Financing Receivable, current year	0	0
Financing Receivable, one year before	0	0
Financing Receivable, two years before	0	0
Financing Receivable, three years before	0	0
Financing Receivable, four years before	0	0
Financing Receivable, prior	67	144
Financing Receivable, revolving	0	0
Watch [Member] | Real Estate Portfolio [Member] | Multi-family Mortgage [Member]
Loans receivable	3,265	7,589
Financing Receivable, current year	0	0
Financing Receivable, one year before	0	647
Financing Receivable, two years before	640	4,104
Financing Receivable, three years before	0	263
Financing Receivable, four years before	260	0
Financing Receivable, prior	2,365	2,575
Financing Receivable, revolving	0	0
Watch [Member] | Real Estate Portfolio [Member] | Nonresidential Real Estate [Member]
Loans receivable	3,259	3,861
Financing Receivable, current year	0	0
Financing Receivable, one year before	0	2,358
Financing Receivable, two years before	1,845	1,503
Financing Receivable, three years before	1,414	0
Financing Receivable, four years before	0	0
Financing Receivable, prior	0	0
Financing Receivable, revolving	0	0
Watch [Member] | Commercial Portfolio Segment [Member]
Loans receivable	13,033	16,761
Financing Receivable, current year	0	6,043
Financing Receivable, one year before	5,630	7,171
Financing Receivable, two years before	6,443	748
Financing Receivable, three years before	718	371
Financing Receivable, four years before	242	0
Financing Receivable, prior	0	0
Financing Receivable, revolving	0	2,428
Watch [Member] | Consumer Portfolio Segment [Member]
Loans receivable	6	7
Financing Receivable, current year	0	0
Financing Receivable, one year before	0	0
Financing Receivable, two years before	0	0
Financing Receivable, three years before	0	0
Financing Receivable, four years before	0	0
Financing Receivable, prior	0	0
Financing Receivable, revolving	6	7
Special Mention [Member]
Loans receivable	11,796	11,925
Special Mention [Member] | Real Estate Portfolio [Member] | One-to-Four Family Residential Real Estate [Member]
Loans receivable	0	0
Special Mention [Member] | Real Estate Portfolio [Member] | Multi-family Mortgage [Member]
Loans receivable	0	1,333
Financing Receivable, current year		118
Financing Receivable, one year before		1,215
Financing Receivable, two years before		0
Financing Receivable, three years before		0
Financing Receivable, four years before		0
Financing Receivable, prior		0
Financing Receivable, revolving		0
Special Mention [Member] | Real Estate Portfolio [Member] | Nonresidential Real Estate [Member]
Loans receivable	433	0
Financing Receivable, current year	0
Financing Receivable, one year before	0
Financing Receivable, two years before	433
Financing Receivable, three years before	0
Financing Receivable, four years before	0
Financing Receivable, prior	0
Financing Receivable, revolving	0
Special Mention [Member] | Commercial Portfolio Segment [Member]
Loans receivable	11,360	10,587
Financing Receivable, current year	0	0
Financing Receivable, one year before	0	0
Financing Receivable, two years before	0	0
Financing Receivable, three years before	0	0
Financing Receivable, four years before	0	0
Financing Receivable, prior	0	0
Financing Receivable, revolving	11,360	10,587
Special Mention [Member] | Consumer Portfolio Segment [Member]
Loans receivable	3	5
Financing Receivable, current year	0	0
Financing Receivable, one year before	0	0
Financing Receivable, two years before	0	0
Financing Receivable, three years before	0	0
Financing Receivable, four years before	0	0
Financing Receivable, prior	0	0
Financing Receivable, revolving	3	5
Substandard [Member]
Loans receivable	5,202	4,331
Substandard [Member] | Real Estate Portfolio [Member] | One-to-Four Family Residential Real Estate [Member]
Loans receivable	167	272
Financing Receivable, current year	0	0
Financing Receivable, one year before	0	0
Financing Receivable, two years before	0	0
Financing Receivable, three years before	0	0
Financing Receivable, four years before	0	0
Financing Receivable, prior	26	127
Financing Receivable, revolving	141	145
Substandard [Member] | Real Estate Portfolio [Member] | Multi-family Mortgage [Member]
Loans receivable	1,421	0
Financing Receivable, current year	0
Financing Receivable, one year before	216
Financing Receivable, two years before	1,205
Financing Receivable, three years before	0
Financing Receivable, four years before	0
Financing Receivable, prior	0
Financing Receivable, revolving	0
Substandard [Member] | Real Estate Portfolio [Member] | Nonresidential Real Estate [Member]
Loans receivable	457	0
Financing Receivable, current year	457
Financing Receivable, one year before	0
Financing Receivable, two years before	0
Financing Receivable, three years before	0
Financing Receivable, four years before	0
Financing Receivable, prior	0
Financing Receivable, revolving	0
Substandard [Member] | Commercial Portfolio Segment [Member]
Loans receivable	3,154	4,056
Financing Receivable, current year	0	0
Financing Receivable, one year before	75	666
Financing Receivable, two years before	146	0
Financing Receivable, three years before	0	22
Financing Receivable, four years before	0	0
Financing Receivable, prior	0	0
Financing Receivable, revolving	2,933	3,368
Substandard [Member] | Consumer Portfolio Segment [Member]
Loans receivable	3	3
Financing Receivable, current year	0	0
Financing Receivable, one year before	0	0
Financing Receivable, two years before	0	0
Financing Receivable, three years before	0	0
Financing Receivable, four years before	0	0
Financing Receivable, prior	0	0
Financing Receivable, revolving	3	3
Substandard Nonaccrual [Member]
Loans receivable	20,814	21,331
Substandard Nonaccrual [Member] | Real Estate Portfolio [Member] | One-to-Four Family Residential Real Estate [Member]
Loans receivable	39	37
Financing Receivable, current year	0	0
Financing Receivable, one year before	0	0
Financing Receivable, two years before	0	0
Financing Receivable, three years before	0	0
Financing Receivable, four years before	0	0
Financing Receivable, prior	23	16
Financing Receivable, revolving	16	21
Substandard Nonaccrual [Member] | Real Estate Portfolio [Member] | Multi-family Mortgage [Member]
Loans receivable	0	0
Substandard Nonaccrual [Member] | Real Estate Portfolio [Member] | Nonresidential Real Estate [Member]
Loans receivable	380	0
Financing Receivable, current year	0
Financing Receivable, one year before	0
Financing Receivable, two years before	380
Financing Receivable, three years before	0
Financing Receivable, four years before	0
Financing Receivable, prior	0
Financing Receivable, revolving	0
Substandard Nonaccrual [Member] | Commercial Portfolio Segment [Member]
Loans receivable	20,395	21,294
Financing Receivable, current year	0	11
Financing Receivable, one year before	356	20,204
Financing Receivable, two years before	19,624	524
Financing Receivable, three years before	0	555
Financing Receivable, four years before	415	0
Financing Receivable, prior	0	0
Financing Receivable, revolving	0	0
Substandard Nonaccrual [Member] | Consumer Portfolio Segment [Member]
Loans receivable	$ 0	$ 0

X

- Definition

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

+ References

No definition available.

+ Details

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- Definition

Amount, excluding accrued interest, of recovery of financing receivable originated more than five years before current fiscal year. Excludes net investment in lease.

+ References

No definition available.

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- Definition

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No definition available.

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- Definition

Amount, excluding accrued interest, of recovery of financing receivable that can be withdrawn, repaid, and redrawn.

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Amount, excluding accrued interest, of recovery (writeoff) of financing receivable that can be withdrawn, repaid, and redrawn.

+ References

No definition available.

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- Definition

Amount, excluding accrued interest, of recovery of financing receivable originated four years before current fiscal year. Excludes net investment in lease.

+ References

No definition available.

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- Definition

Amount, excluding accrued interest, of recovery (writeoff) of financing receivable originated four years before current fiscal year. Excludes net investment in lease.

+ References

No definition available.

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- Definition

Amount, excluding accrued interest, of recovery of financing receivable originated three years before current fiscal year. Excludes net investment in lease.

+ References

No definition available.

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- Definition

Amount, excluding accrued interest, of recovery (writeoff) of financing receivable originated three years before current fiscal year. Excludes net investment in lease.

+ References

No definition available.

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- Definition

Amount, excluding accrued interest, of recovery of financing receivable originated in current fiscal year. Excludes net investment in lease.

+ References

No definition available.

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- Definition

Amount, excluding accrued interest, of recovery (writeoff) of financing receivable originated in current fiscal year. Excludes net investment in lease.

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No definition available.

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- Definition

Amount, excluding accrued interest, of recovery of financing receivable originated two years before current fiscal year. Excludes net investment in lease.

+ References

No definition available.

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Amount, excluding accrued interest, of recovery (writeoff) of financing receivable originated two years before current fiscal year. Excludes net investment in lease.

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No definition available.

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Amount, excluding accrued interest, of recovery of financing receivable originated in fiscal year before current fiscal year. Excludes net investment in lease.

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No definition available.

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- Definition

Amount, excluding accrued interest, of recovery (writeoff) of financing receivable originated in fiscal year before current fiscal year. Excludes net investment in lease.

+ References

No definition available.

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- Definition

Amortized cost, before allowance for credit loss, fee, and loan in process, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481990/310-10-45-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-5

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(7))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

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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 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-6

Reference 2: 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

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X

- Definition

Amount, excluding accrued interest, of writeoff of financing receivable originated more than five years before current fiscal year. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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