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Note 3 - Loans Receivable and Allowance for Credit Losses - Loans - - Schedule of Modified Financing Receivables (Details) - Commercial Real Estate Portfolio Segment [Member] - Commercial Loan [Member] - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
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Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Financing Receivable, Excluding Accrued Interest, Modified in Period, to Total Financing Receivables, Percentage | 0.70% | 0.30% | 0.70% | 0.30%
Extended Maturity and Payment Delay [Member] |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified in Period, Amount | $ 1,203 | $ 1,130 | $ 1,203 | $ 1,130
Extended Maturity [Member] |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified, Weighted Average Term Extension Payment Delay (Year) | 3 years 3 months 18 days | 2 years 3 months 18 days | 3 years 3 months 18 days | 2 years 3 months 18 days

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- Definition Period of increase in weighted average maturity of financing receivable modified (excluding accrued interest) for debtor experiencing financial difficulty, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days + References No definition available. + Details
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- Definition Amortized cost excluding accrued interest, of financing receivable modified during period for debtor experiencing financial difficulty. + References Reference 1: 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 Percentage, excluding accrued interest, of financing receivable modified during period for debtor experiencing financial difficulty to total financing receivables. + References Reference 1: 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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