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Note 4 - Loans Receivable - Risk Categories of Loans By Class of Loans (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2024	Dec. 31, 2023
Loans receivable	$ 1,016,229	$ 1,059,106
Real Estate Portfolio [Member] | One-to-Four Family Residential Real Estate [Member]
Loans receivable	18,247	18,945
Financing Receivable, current year	0	489
Financing Receivable, one year before	488	0
Financing Receivable, two years before	0	0
Financing Receivable, three years before	0	130
Financing Receivable, four years before	107	0
Financing Receivable, prior	13,899	14,356
Financing Receivable, revolving	3,753	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	3	45
Current period recoveries, revolving	0	0
Current period recoveries, total	3	45
Recoveries (charge-offs), net, current year	0	0
Recoveries (charge-offs), net, one year before	0	0
Recoveries (charge-offs), net, two year before	0	0
Recoveries (charge-offs), net, three year before	0	0
Recoveries (charge-offs), net, four years before	0	0
Recoveries (charge-offs), net, prior	3	44
Recoveries (charge-offs), net, revolving	0	0
Recoveries (charge-offs), net, total	3	44
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)
Real Estate Portfolio [Member] | Multi-family Mortgage [Member]
Loans receivable	526,087	527,460
Financing Receivable, current year	5,309	43,504
Financing Receivable, one year before	43,347	212,740
Financing Receivable, two years before	211,496	112,667
Financing Receivable, three years before	111,918	57,743
Financing Receivable, four years before	57,120	22,064
Financing Receivable, prior	88,715	70,007
Financing Receivable, revolving	8,182	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	6	20
Current period recoveries, revolving	0	0
Current period recoveries, total	6	20
Recoveries (charge-offs), net, current year	0	0
Recoveries (charge-offs), net, one year before	0	0
Recoveries (charge-offs), net, two year before	0	0
Recoveries (charge-offs), net, three year before	0	0
Recoveries (charge-offs), net, four years before	0	0
Recoveries (charge-offs), net, prior	6	20
Recoveries (charge-offs), net, revolving	0	0
Recoveries (charge-offs), net, total	6	20
Real Estate Portfolio [Member] | Nonresidential Real Estate [Member]
Loans receivable	110,319	118,016
Financing Receivable, current year	8,975	17,618
Financing Receivable, one year before	15,491	53,256
Financing Receivable, two years before	49,103	21,939
Financing Receivable, three years before	16,716	7,787
Financing Receivable, four years before	7,672	9,024
Financing Receivable, prior	12,260	8,288
Financing Receivable, revolving	102	104
Commercial Portfolio Segment [Member]
Loans receivable	360,328	393,321
Financing Receivable, current year	3,386	50,026
Financing Receivable, one year before	44,822	158,485
Financing Receivable, two years before	144,051	63,552
Financing Receivable, three years before	55,012	33,581
Financing Receivable, four years before	28,512	3,028
Financing Receivable, prior	2,944	1,379
Financing Receivable, revolving	81,601	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	0	0
Current period recoveries, prior	0	0
Current period recoveries, revolving	0	0
Current period recoveries, total	5	77
Recoveries (charge-offs), net, current year	0	(20)
Recoveries (charge-offs), net, one year before	(1)	(1,850)
Recoveries (charge-offs), net, two year before	(109)	37
Recoveries (charge-offs), net, three year before	(38)	(266)
Recoveries (charge-offs), net, four years before	(5)	0
Recoveries (charge-offs), net, prior	0	0
Recoveries (charge-offs), net, revolving	0	0
Recoveries (charge-offs), net, total	(153)	(2,099)
Current period gross charge-offs	0	(20)
Current period gross charge-offs	(1)	(1,850)
Current period gross charge-offs	(109)	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	(158)	(2,176)
Consumer Portfolio Segment [Member]
Loans receivable	1,248	1,364
Financing Receivable, current year	14	336
Financing Receivable, one year before	229	8
Financing Receivable, two years before	7	140
Financing Receivable, three years before	138	80
Financing Receivable, four years before	79	247
Financing Receivable, prior	198	0
Financing Receivable, revolving	583	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
Recoveries (charge-offs), net, current year	0	0
Recoveries (charge-offs), net, one year before	0	0
Recoveries (charge-offs), net, two year before	0	0
Recoveries (charge-offs), net, three year before	0	0
Recoveries (charge-offs), net, four years before	0	0
Recoveries (charge-offs), net, prior	0	0
Recoveries (charge-offs), net, revolving	(13)	(51)
Recoveries (charge-offs), net, total	(13)	(51)
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	(13)	(52)
Current period gross charge-offs	(13)	(52)
Pass [Member]
Loans receivable	953,824	993,157
Pass [Member] | Real Estate Portfolio [Member] | One-to-Four Family Residential Real Estate [Member]
Loans receivable	17,945	18,492
Financing Receivable, current year	0	489
Financing Receivable, one year before	488	0
Financing Receivable, two years before	0	0
Financing Receivable, three years before	0	130
Financing Receivable, four years before	107	0
Financing Receivable, prior	13,758	14,069
Financing Receivable, revolving	3,592	3,804
Pass [Member] | Real Estate Portfolio [Member] | Multi-family Mortgage [Member]
Loans receivable	517,153	518,538
Financing Receivable, current year	5,309	43,386
Financing Receivable, one year before	43,174	210,878
Financing Receivable, two years before	209,640	108,563
Financing Receivable, three years before	107,835	57,480
Financing Receivable, four years before	56,859	22,064
Financing Receivable, prior	86,154	67,432
Financing Receivable, revolving	8,182	8,735
Pass [Member] | Real Estate Portfolio [Member] | Nonresidential Real Estate [Member]
Loans receivable	105,444	114,155
Financing Receivable, current year	7,845	17,618
Financing Receivable, one year before	15,491	50,898
Financing Receivable, two years before	46,817	20,436
Financing Receivable, three years before	15,257	7,787
Financing Receivable, four years before	7,672	9,024
Financing Receivable, prior	12,260	8,288
Financing Receivable, revolving	102	104
Pass [Member] | Commercial Portfolio Segment [Member]
Loans receivable	312,045	340,623
Financing Receivable, current year	3,386	43,972
Financing Receivable, one year before	39,005	130,444
Financing Receivable, two years before	117,372	62,280
Financing Receivable, three years before	54,076	32,633
Financing Receivable, four years before	27,732	3,028
Financing Receivable, prior	2,944	1,379
Financing Receivable, revolving	67,530	66,887
Pass [Member] | Consumer Portfolio Segment [Member]
Loans receivable	1,237	1,349
Financing Receivable, current year	14	336
Financing Receivable, one year before	229	8
Financing Receivable, two years before	7	140
Financing Receivable, three years before	138	80
Financing Receivable, four years before	79	247
Financing Receivable, prior	198	0
Financing Receivable, revolving	572	538
Watch [Member]
Loans receivable	27,740	28,362
Watch [Member] | Real Estate Portfolio [Member] | One-to-Four Family Residential Real Estate [Member]
Loans receivable	64	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	64	144
Financing Receivable, revolving	0	0
Watch [Member] | Real Estate Portfolio [Member] | Multi-family Mortgage [Member]
Loans receivable	7,548	7,589
Financing Receivable, current year	0	0
Financing Receivable, one year before	0	647
Financing Receivable, two years before	643	4,104
Financing Receivable, three years before	4,083	263
Financing Receivable, four years before	261	0
Financing Receivable, prior	2,561	2,575
Financing Receivable, revolving	0	0
Watch [Member] | Real Estate Portfolio [Member] | Nonresidential Real Estate [Member]
Loans receivable	3,974	3,861
Financing Receivable, current year	665	0
Financing Receivable, one year before	0	2,358
Financing Receivable, two years before	1,850	1,503
Financing Receivable, three years before	1,459	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	16,150	16,761
Financing Receivable, current year	0	6,043
Financing Receivable, one year before	5,806	7,171
Financing Receivable, two years before	6,731	748
Financing Receivable, three years before	488	371
Financing Receivable, four years before	279	0
Financing Receivable, prior	0	0
Financing Receivable, revolving	2,846	2,428
Watch [Member] | Consumer Portfolio Segment [Member]
Loans receivable	4	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	4	7
Special Mention [Member]
Loans receivable	9,876	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	1,386	1,333
Financing Receivable, current year	0	118
Financing Receivable, one year before	173	1,215
Financing Receivable, two years before	1,213	0
Financing Receivable, three years before	0	0
Financing Receivable, four years before	0	0
Financing Receivable, prior	0	0
Financing Receivable, revolving	0	0
Special Mention [Member] | Real Estate Portfolio [Member] | Nonresidential Real Estate [Member]
Loans receivable	436	0
Financing Receivable, current year	0
Financing Receivable, one year before	0
Financing Receivable, two years before	436
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	8,052	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	8,052	10,587
Special Mention [Member] | Consumer Portfolio Segment [Member]
Loans receivable	2	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	2	5
Substandard [Member]
Loans receivable	4,280	4,331
Substandard [Member] | Real Estate Portfolio [Member] | One-to-Four Family Residential Real Estate [Member]
Loans receivable	204	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	62	127
Financing Receivable, revolving	142	145
Substandard [Member] | Real Estate Portfolio [Member] | Multi-family Mortgage [Member]
Loans receivable	0	0
Substandard [Member] | Real Estate Portfolio [Member] | Nonresidential Real Estate [Member]
Loans receivable	465	0
Financing Receivable, current year	465
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	3,606	4,056
Financing Receivable, current year	0	0
Financing Receivable, one year before	0	666
Financing Receivable, two years before	409	0
Financing Receivable, three years before	11	22
Financing Receivable, four years before	13	0
Financing Receivable, prior	0	0
Financing Receivable, revolving	3,173	3,368
Substandard [Member] | Consumer Portfolio Segment [Member]
Loans receivable	5	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	5	3
Substandard Nonaccrual [Member]
Loans receivable	20,509	21,331
Substandard Nonaccrual [Member] | Real Estate Portfolio [Member] | One-to-Four Family Residential Real Estate [Member]
Loans receivable	34	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	15	16
Financing Receivable, revolving	19	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	0	0
Substandard Nonaccrual [Member] | Commercial Portfolio Segment [Member]
Loans receivable	20,475	21,294
Financing Receivable, current year	0	11
Financing Receivable, one year before	11	20,204
Financing Receivable, two years before	19,539	524
Financing Receivable, three years before	437	555
Financing Receivable, four years before	488	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

Amount, excluding accrued interest, of recovery (writeoff) 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

Amount, excluding accrued interest, of recovery 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 (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.

+ Details

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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.

+ References

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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- Definition

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

+ References

No definition available.

+ Details

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X

- 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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X

- 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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X

- 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

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