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Note 3 - Loans Receivable and Allowance for Credit Losses - Loans (Details Textual) - USD ($) | 3 Months Ended | 15 Months Ended |
--- | --- | --- | ---
Mar. 31, 2025 | Mar. 31, 2024 | Mar. 31, 2025 | Dec. 31, 2024
Financing Receivable, Unamortized Loan Cost (Fee) | $ (5,800,000) |  | $ (5,800,000) | $ (6,000,000)
Financing Receivable, Unamortized Purchase Premium (Discount) | 1,900,000 |  | 1,900,000 | 2,000,000
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss | 2,532,770,000 |  | 2,532,770,000 | 2,533,821,000
Financing Receivable, Modified, Commitment to Lend | 3,800,000 |  | 3,800,000 |
Financing Receivable, Modified, Subsequent Default |  |  | 0 |
Financing Receivable, 90 Days or More Past Due, Still Accruing | 0 |  | 0 | 0
Financing Receivable, Nonaccrual, Interest Income | 105,000 | $ 111,000 |  |
Real Estate Owned (OREO) [Member] |  |  |  |
Mortgage Loans in Process of Foreclosure, Amount | 977,000 |  | 977,000 | 84,000
Commercial Business Portfolio Segment [Member] |  |  |  |
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss | 290,905,000 |  | 290,905,000 | 299,932,000
Commercial Business Portfolio Segment [Member] | Commercial And Industrial [Member] |  |  |  |
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss | 274,956,000 |  | 274,956,000 | 287,014,000
Commercial Business Portfolio Segment [Member] | Commercial And Industrial [Member] | SBA USDA Guaranteed Certificates [Member] |  |  |  |
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss | 51,600,000 |  | 51,600,000 | 52,600,000
Asset Pledged as Collateral [Member] | Federal Home Loan Bank Advances [Member] |  |  |  |
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss | 1,080,000,000.00 |  | 1,080,000,000.00 | 1,110,000,000
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 | $ 597,400,000 |  | $ 597,400,000 | $ 606,500,000

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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://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 2: 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 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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- Definition Amortized cost of financing receivable 90 days or more past due and still accruing. Excludes net investment in lease. + References Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 7 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481962/310-10-50-7 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 80 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479294/326-20-55-80 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 16 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-16 + Details
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- Definition 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. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 310 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481598/310-20-45-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481962/310-10-50-4 Reference 3: http://www.xbrl.org/2003/role/recommendedDisclosureRef -Name Accounting Standards Codification -Section 50 -Paragraph 3 -SubTopic 20 -Topic 310 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481569/310-20-50-3 + Details
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