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Note 4 - Loans Receivable - Risk Categories of Loans By Class of Loans (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2023	Dec. 31, 2022
Loans receivable	$ 1,179,993	$ 1,234,872
Real Estate Portfolio [Member] | One-to-Four Family Residential Real Estate [Member]
Loans receivable	20,448	23,133
Financing Receivable, current year	0
Financing Receivable, one year before	0
Financing Receivable, two years before	0
Financing Receivable, three years before	177
Financing Receivable, four years before	0
Financing Receivable, prior	15,878
Financing Receivable, revolving	4,393
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	12
Current period recoveries, revolving	0
Current period recoveries, total	12
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year, Recovery (Writeoff), Net	0
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year, Recovery (Writeoff), Net	0
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year, Recovery (Writeoff), Net	0
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year, Recovery (Writeoff), Net	0
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year, Recovery (Writeoff), Net	0
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year, Recovery (Writeoff), Net	12
Financing Receivable, Excluding Accrued Interest, Revolving, Recovery (Writeoff), Net	0
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Recovery (Writeoff), Net	12
Real Estate Portfolio [Member] | Multi-family Mortgage [Member]
Loans receivable	542,165	537,394
Financing Receivable, current year	30,387
Financing Receivable, one year before	215,111
Financing Receivable, two years before	124,335
Financing Receivable, three years before	61,456
Financing Receivable, four years before	23,685
Financing Receivable, prior	78,560
Financing Receivable, revolving	8,631
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	11
Current period recoveries, revolving	0
Current period recoveries, total	11
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year, Recovery (Writeoff), Net	0
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year, Recovery (Writeoff), Net	0
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year, Recovery (Writeoff), Net	0
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year, Recovery (Writeoff), Net	0
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year, Recovery (Writeoff), Net	0
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year, Recovery (Writeoff), Net	11
Financing Receivable, Excluding Accrued Interest, Revolving, Recovery (Writeoff), Net	0
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Recovery (Writeoff), Net	11
Real Estate Portfolio [Member] | Nonresidential Real Estate [Member]
Loans receivable	120,505	119,705
Financing Receivable, current year	9,525
Financing Receivable, one year before	55,222
Financing Receivable, two years before	22,412
Financing Receivable, three years before	8,542
Financing Receivable, four years before	9,868
Financing Receivable, prior	14,682
Financing Receivable, revolving	254
Commercial Portfolio Segment [Member]
Loans receivable	495,520	553,056
Financing Receivable, current year	30,242
Financing Receivable, one year before	212,483
Financing Receivable, two years before	92,244
Financing Receivable, three years before	60,608
Financing Receivable, four years before	6,914
Financing Receivable, prior	3,871
Financing Receivable, revolving	89,158
Current period recoveries, current year	0
Current period recoveries, one year before	0
Current period recoveries, two years before	7
Current period recoveries, three years before	0
Current period recoveries, four years before	0
Current period recoveries, prior	0
Current period recoveries, revolving	0
Current period recoveries, total	7
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year, Recovery (Writeoff), Net	0
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year, Recovery (Writeoff), Net	(717)
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year, Recovery (Writeoff), Net	7
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year, Recovery (Writeoff), Net	0
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year, Recovery (Writeoff), Net	0
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year, Recovery (Writeoff), Net	0
Financing Receivable, Excluding Accrued Interest, Revolving, Recovery (Writeoff), Net	0
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Recovery (Writeoff), Net	(710)
Current period gross charge-offs	0
Current period gross charge-offs	(717)
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	(717)
Consumer Portfolio Segment [Member]
Loans receivable	1,355	1,584
Financing Receivable, current year	134
Financing Receivable, one year before	18
Financing Receivable, two years before	172
Financing Receivable, three years before	159
Financing Receivable, four years before	306
Financing Receivable, prior	3
Financing Receivable, revolving	563
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
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year, Recovery (Writeoff), Net	0
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year, Recovery (Writeoff), Net	0
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year, Recovery (Writeoff), Net	0
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year, Recovery (Writeoff), Net	0
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year, Recovery (Writeoff), Net	0
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year, Recovery (Writeoff), Net	0
Financing Receivable, Excluding Accrued Interest, Revolving, Recovery (Writeoff), Net	(28)
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Recovery (Writeoff), Net	(28)
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	0
Current period gross charge-offs	(29)
Current period gross charge-offs	(29)
Pass [Member]
Loans receivable	1,130,289	1,198,984
Pass [Member] | Real Estate Portfolio [Member] | One-to-Four Family Residential Real Estate [Member]
Loans receivable	19,988	22,648
Financing Receivable, current year	0
Financing Receivable, one year before	0
Financing Receivable, two years before	0
Financing Receivable, three years before	177
Financing Receivable, four years before	0
Financing Receivable, prior	15,595
Financing Receivable, revolving	4,216
Pass [Member] | Real Estate Portfolio [Member] | Multi-family Mortgage [Member]
Loans receivable	539,400	534,253
Financing Receivable, current year	30,387
Financing Receivable, one year before	215,111
Financing Receivable, two years before	124,335
Financing Receivable, three years before	61,456
Financing Receivable, four years before	23,685
Financing Receivable, prior	75,795
Financing Receivable, revolving	8,631
Pass [Member] | Real Estate Portfolio [Member] | Nonresidential Real Estate [Member]
Loans receivable	117,558	116,635
Financing Receivable, current year	9,525
Financing Receivable, one year before	54,207
Financing Receivable, two years before	20,822
Financing Receivable, three years before	8,542
Financing Receivable, four years before	9,868
Financing Receivable, prior	14,340
Financing Receivable, revolving	254
Pass [Member] | Commercial Portfolio Segment [Member]
Loans receivable	452,002	523,889
Financing Receivable, current year	30,242
Financing Receivable, one year before	187,329
Financing Receivable, two years before	91,671
Financing Receivable, three years before	59,239
Financing Receivable, four years before	6,888
Financing Receivable, prior	3,871
Financing Receivable, revolving	72,762
Pass [Member] | Consumer Portfolio Segment [Member]
Loans receivable	1,341	1,559
Financing Receivable, current year	134
Financing Receivable, one year before	18
Financing Receivable, two years before	172
Financing Receivable, three years before	159
Financing Receivable, four years before	306
Financing Receivable, prior	3
Financing Receivable, revolving	549
Watch [Member]
Loans receivable	19,362	28,584
Watch [Member] | Real Estate Portfolio [Member] | One-to-Four Family Residential Real Estate [Member]
Loans receivable	143	62
Financing Receivable, current year	0
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	143
Financing Receivable, revolving	0
Watch [Member] | Real Estate Portfolio [Member] | Multi-family Mortgage [Member]
Loans receivable	2,617	3,141
Financing Receivable, current year	0
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	2,617
Financing Receivable, revolving	0
Watch [Member] | Real Estate Portfolio [Member] | Nonresidential Real Estate [Member]
Loans receivable	2,947	3,070
Financing Receivable, current year	0
Financing Receivable, one year before	1,015
Financing Receivable, two years before	1,590
Financing Receivable, three years before	0
Financing Receivable, four years before	0
Financing Receivable, prior	342
Financing Receivable, revolving	0
Watch [Member] | Commercial Portfolio Segment [Member]
Loans receivable	13,651	22,299
Financing Receivable, current year	0
Financing Receivable, one year before	527
Financing Receivable, two years before	26
Financing Receivable, three years before	402
Financing Receivable, four years before	26
Financing Receivable, prior	0
Financing Receivable, revolving	12,670
Watch [Member] | Consumer Portfolio Segment [Member]
Loans receivable	4	12
Financing Receivable, current year	0
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	4
Special Mention [Member]
Loans receivable	2,148	1,525
Special Mention [Member] | Real Estate Portfolio [Member] | One-to-Four Family Residential Real Estate [Member]
Loans receivable	0	4
Special Mention [Member] | Real Estate Portfolio [Member] | Multi-family Mortgage [Member]
Loans receivable	0	0
Special Mention [Member] | Real Estate Portfolio [Member] | Nonresidential Real Estate [Member]
Loans receivable	0	0
Special Mention [Member] | Commercial Portfolio Segment [Member]
Loans receivable	2,143	1,517
Financing Receivable, current year	0
Financing Receivable, one year before	2,143
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] | Consumer Portfolio Segment [Member]
Loans receivable	5	4
Financing Receivable, current year	0
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	5
Substandard [Member]
Loans receivable	4,036	4,372
Substandard [Member] | Real Estate Portfolio [Member] | One-to-Four Family Residential Real Estate [Member]
Loans receivable	272	327
Financing Receivable, current year	0
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	121
Financing Receivable, revolving	151
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	0	0
Substandard [Member] | Commercial Portfolio Segment [Member]
Loans receivable	3,759	4,041
Financing Receivable, current year	0
Financing Receivable, one year before	0
Financing Receivable, two years before	0
Financing Receivable, three years before	33
Financing Receivable, four years before	0
Financing Receivable, prior	0
Financing Receivable, revolving	3,726
Substandard [Member] | Consumer Portfolio Segment [Member]
Loans receivable	5	4
Financing Receivable, current year	0
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	5
Substandard Nonaccrual [Member]
Loans receivable	24,158	1,407
Substandard Nonaccrual [Member] | Real Estate Portfolio [Member] | One-to-Four Family Residential Real Estate [Member]
Loans receivable	45	92
Financing Receivable, current year	0
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	19
Financing Receivable, revolving	26
Substandard Nonaccrual [Member] | Real Estate Portfolio [Member] | Multi-family Mortgage [Member]
Loans receivable	148	0
Financing Receivable, current year	0
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	148
Financing Receivable, revolving	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	23,965	1,310
Financing Receivable, current year	0
Financing Receivable, one year before	22,484
Financing Receivable, two years before	547
Financing Receivable, three years before	934
Financing Receivable, four years before	0
Financing Receivable, prior	0
Financing Receivable, revolving	0
Substandard Nonaccrual [Member] | Consumer Portfolio Segment [Member]
Loans receivable	$ 0	$ 5

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.

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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.

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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.

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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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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.

+ Details

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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.

+ 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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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.

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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/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 2: 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 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//1943274/2147479853/942-210-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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- 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
-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 writeoff of financing receivable that can be withdrawn, repaid, and redrawn.

+ 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

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