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Note 4 - Loans Receivable and Allowance for Credit Losses on Loans (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Financing Receivable, Unamortized Loan Cost (Fee)	$ (6,000,000)	$ (8,400,000)
Financing Receivable, Unamortized Purchase Premium (Discount)	2,000,000	2,600,000
Financing Receivable, Accrued Interest, after Allowance for Credit Loss	12,200,000	11,500,000
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	2,533,821,000	2,433,015,000
Financing Receivable, Modified, Commitment to Lend	5,300,000
Financing Receivable, Modified, Subsequent Default	0	0
Financing Receivable, 90 Days or More Past Due, Still Accruing	0	0
Financing Receivable, Nonaccrual, Interest Income	427,000	579,000	$ 506,000
Loans and Leases Receivable, Commitment to Lend, Related Party	$ 3,600,000	$ 3,700,000
Financing Receivable, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration]	Interest Receivable	Interest Receivable
Commercial Business Portfolio Segment [Member]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	$ 299,932,000	$ 255,881,000
Commercial Business Portfolio Segment [Member] | Commercial And Industrial [Member]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	287,014,000	238,301,000
Commercial Business Portfolio Segment [Member] | Commercial And Industrial [Member] | SBA USDA Guaranteed Certificates [Member]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	52,600,000	10,600,000
Asset Pledged as Collateral [Member] | Federal Home Loan Bank Advances [Member]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	1,110,000,000	1,070,000,000.00
Asset Pledged as Collateral [Member] | Federal Reserve Bank [Member] | Federal Reserve Bank of San Francisco [Member]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	$ 606,500,000	$ 631,100,000

X

- Definition

The amount of loans and leases receivable, commitment to lend, related party.

+ References

No definition available.

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Amount, after allowance for credit loss, of accrued interest on financing receivable.

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- Definition

Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

+ References

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Amortized cost of financing receivable with payment default in current period and modified within previous 12 months preceding payment default for debtor experiencing financial difficulty.

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Amount of interest income on financing receivable on nonaccrual status.

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Amount of unamortized loan commitment, origination, and other costs (fees) on financing receivable recognized as adjustment to yield. Excludes financing receivable covered under loss sharing agreement.

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