Note 4 - Loans (Details Textual)	3 Months Ended	12 Months Ended
Mar. 31, 2025 USD ($)	Dec. 31, 2024 USD ($)
Financing Receivable, before Allowance for Credit Loss, Fee and Loan in Process	$ 3,163,934,000	$ 3,221,607,000
Number of Loans In Process Of Foreclosure	1	0
Mortgage Loans in Process of Foreclosure, Amount	$ 844,000
Interest Receivable	10,800,000	$ 10,700,000
Financing Receivable, Modified in Period, Amount	$ 0
Minimum Prior Year Principal Balance Of Commercial Real Estate Loans Required To Be Reviewed Annually	80.00%
Company's Minimum Credit Score Required For New Loans	680
Financial Asset, Closed Portfolio and Beneficial Interest, Portfolio Layer Method, Amortized Cost	$ 58,000
Commercial Real Estate Portfolio Segment [Member] \| Multifamily Loan [Member]
Financing Receivable, before Allowance for Credit Loss, Fee and Loan in Process	840,726,000	848,558,000
Commercial Real Estate Portfolio Segment [Member] \| Owner Occupied Loan 1 [Member]
Financing Receivable, before Allowance for Credit Loss, Fee and Loan in Process	247,326,000	263,272,000
Commercial Portfolio Segment [Member]
Financing Receivable, before Allowance for Credit Loss, Fee and Loan in Process	134,095,000	136,732,000
Financing Receivable, Revolving, Converted to Term Loan	4,300,000
Commercial Portfolio Segment [Member] \| Owner Occupied Loan 1 [Member]
Financing Receivable, Revolving, Converted to Term Loan	1,000,000
Residential Portfolio Segment [Member]
Financing Receivable, Revolving, Converted to Term Loan	6,900,000
Financial Asset, 30 to 59 Days Past Due [Member]
Increase (Decrease) in Past Due Financing Receivable	7,200,000
Financing Receivable, before Allowance for Credit Loss, Fee and Loan in Process	7,452,000	174,000
Financial Asset, 30 to 59 Days Past Due [Member] \| Commercial Real Estate Portfolio Segment [Member] \| Multifamily Loan [Member]
Financing Receivable, before Allowance for Credit Loss, Fee and Loan in Process	6,798,000	0
Financial Asset, 30 to 59 Days Past Due [Member] \| Commercial Real Estate Portfolio Segment [Member] \| Owner Occupied Loan 1 [Member]
Financing Receivable, before Allowance for Credit Loss, Fee and Loan in Process	95,000	0
Financial Asset, 30 to 59 Days Past Due [Member] \| Commercial Portfolio Segment [Member]
Financing Receivable, before Allowance for Credit Loss, Fee and Loan in Process	$ 0	$ 174,000
Minimum [Member]
Adjustments to Historical Loss Information, Forecasting Horizon, Period (Year)	1 year
Maximum [Member]
Adjustments to Historical Loss Information, Forecasting Horizon, Period (Year)	2 years

The period for adjustments to historical loss information in the forecasting horizon.

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- Definition

The minimum credit score required for new loans.

+ References

No definition available.

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- Definition

The amount of increase (decrease) in past due financing receivables.

+ References

No definition available.

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- Definition

Represents the percentage of the minimum prior year principal balance of commercial real estate loans that is required to be reviewed annually.

+ References

No definition available.

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- Definition

The number of loans in process of foreclosure.

+ References

No definition available.

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- Definition

Amortized cost of closed portfolio of financial asset and beneficial interest secured by financial instrument, used to designate hedging relationship in which hedged item is expected to be outstanding for designated hedge period.

+ References

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

Amortized cost of financing receivable modified during period for debtor experiencing financial difficulty.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition

Amortized cost of revolving financing receivable converted to term loan.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition

Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

+ References

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