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Note 16 - Commitments and Contingencies - Summary of Tax Credits and Certain Equity Method Investments (Details) (Parentheticals) | 12 Months Ended
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Dec. 31, 2025 | Dec. 31, 2024
Investment Program, Proportional Amortization Method, Elected, Income Tax Credit and Other Income Tax Benefit, before Amortization, Statement of Income or Comprehensive Income [Extensible Enumeration] | Provision for income taxes | Provision for income taxes
Investment Program, Proportional Amortization Method, Elected, Income Tax Credit and Other Income Tax Benefit, before Amortization, Statement of Cash Flows [Extensible Enumeration] | Deferred tax expense (benefit) | Deferred tax expense (benefit)
Investment Program, Proportional Amortization Method, Applied, Amortization Expense, Statement of Income or Comprehensive Income [Extensible Enumeration] | Other operating expenses | Other operating expenses
Affordable Housing Projects [Member] |  |
Investment, Proportional Amortization Method, Elected, Statement of Financial Position [Extensible Enumeration] | Other assets | Other assets
SBIC and Other Equity Method Investments [Member] |  |
Investment, Proportional Amortization Method, Elected, Statement of Financial Position [Extensible Enumeration] | Other assets | Other assets

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- Definition Indicates line item in statement of income or comprehensive income that includes amortization expense for investment that generates income tax credit and other income tax benefit under tax credit program accounted for using proportional amortization method. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 740 -SubTopic 323 -Name Accounting Standards Codification -Section 50 -Paragraph 1A -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478156/740-323-50-1A + Details
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- Definition Indicates line item in statement of cash flows that includes income tax credit and other income tax benefit, before amortization expense, generated by investment under tax credit program elected to be accounted for using proportional amortization method. Includes, but is not limited to, investment under tax credit program not meeting condition for accounting under proportional amortization method. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 740 -SubTopic 323 -Name Accounting Standards Codification -Section 50 -Paragraph 1A -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478156/740-323-50-1A + Details
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- Definition Indicates line item in statement of income or comprehensive income that includes income tax credit and other income tax benefit, before amortization expense, generated by investment under tax credit program elected to be accounted for using proportional amortization method. Includes, but is not limited to, investment under tax credit program not meeting condition for accounting under proportional amortization method. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 740 -SubTopic 323 -Name Accounting Standards Codification -Section 50 -Paragraph 1A -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478156/740-323-50-1A + Details
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- Definition Indicates line item in statement of financial position that includes investment that generates income tax credit and other income tax benefit under tax credit program elected to be accounted for using proportional amortization method. Includes, but is not limited to, investment under tax credit program not meeting condition for accounting under proportional amortization method. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 740 -SubTopic 323 -Name Accounting Standards Codification -Section 50 -Paragraph 1A -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478156/740-323-50-1A + Details
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