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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 |

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- Definition Amount, after allowance for credit loss, of accrued interest on financing receivable. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 5 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479344/326-20-45-5 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3A -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-3A + Details
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- Definition Indicates line item in statement of financial position that includes accrued interest, after allowance for credit loss, on financing receivable. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3A -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-3A + Details
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- Definition Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479344/326-20-45-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3B -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-3B Reference 3: 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 + Details
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- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 34 -Subparagraph (a)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481962/310-10-50-34 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 12A -Publisher FASB -URI https://asc.fasb.org/1943274/2147481933/310-10-55-12A Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 44 -Subparagraph (a)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481962/310-10-50-44 + Details
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