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Note 4 - Loans Receivable and Allowance for Credit Losses - Loans (Details Textual) Pure in Thousands | 3 Months Ended |
--- | --- | ---
Mar. 31, 2024 USD ($) | Mar. 31, 2023 USD ($) | Dec. 31, 2023 USD ($)
Assets [Abstract] |  |  |
Interest Receivable | $ 14,455,000 |  | $ 14,005,000
Financing Receivable, Unamortized Loan Cost (Fee) | (7,500,000) |  | (8,400,000)
Financing Receivable, Unamortized Purchase Premium (Discount) | 2,400,000 |  | 2,600,000
Financing Receivable, Accrued Interest, after Allowance for Credit Loss | $ 11,600,000 |  | $ 11,500,000
Financing Receivable, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration] | Interest Receivable |  | Interest Receivable
Financing Receivable, before Allowance for Credit Loss | $ 2,446,858,000 |  | $ 2,433,015,000
Financing Receivable, Modified, Subsequent Default, Number of Contracts | 0 | 0 |
Financing Receivable, Modified, Commitment to Lend | $ 0 |  |
Financing Receivable, 90 Days or More Past Due, Still Accruing | 0 |  | 0
Financing Receivable, Nonaccrual, Interest Income | 111,000 | $ 62,000 |
Asset Pledged as Collateral [Member] | Federal Home Loan Bank Advances [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss | 1,090,000,000.00 |  | 1,070,000,000.00
Asset Pledged as Collateral [Member] | Federal Home Loan Bank Advances [Member] | Federal Home Loan Bank of San Francisco [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss | $ 632,800,000 |  | $ 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 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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