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Note 4 - Loans Receivable and Allowance for Credit Losses on Loans - Loan Modifications to Borrowers Experiencing Financial Difficulty (Details) - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2024 | Mar. 31, 2023
Commercial Real Estate Portfolio Segment [Member] | Payment Deferral [Member] |  |
Amortized cost basis | $ 1,102 |
% of total loan type | 0.30% |
Weighted-average period (Year) | 1 year 8 months 12 days |
Commercial And Industrial [Member] | Commercial Business Portfolio Segment [Member] | Extended Maturity and Interest Rate Reduction [Member] |  |
Amortized cost basis |  | $ 3,709
% of total loan type |  | 1.70%
Weighted-average period (Year) |  | 5 years
Pre-modification % |  | 7.50%
Post-modification % |  | 4.10%

X
- Definition Percentage of original weighted average contractual interest rate of financing receivable modified for debtor experiencing financial difficulty. + References No definition available. + Details
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X
- Definition Percentage of post-modification weighted average contractual interest rate of financing receivable modified for debtor experiencing financial difficulty. + References No definition available. + Details
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X
- Definition Percentage of financing receivable modified during period for debtor experiencing financial difficulty to total financing receivables. + 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://www.xbrl.org/2003/role/disclosureRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 42 -Subparagraph (a)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481962/310-10-50-42 + Details
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- Definition Period of increase in weighted average maturity of financing receivable modified for debtor experiencing financial difficulty, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + 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 + Details
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