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Note 1 - Summary of Significant Accounting Policies (Details Textual) - USD ($) shares in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2025 | Dec. 31, 2024
Summary of Significant Accounting Policies [Line Items] |  |
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss | $ 3,177,000 | $ 3,171,000
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration] | Securities available-for-sale, fair values | Securities available-for-sale, fair values
Discount on acquired loans | $ 989,418,000 | $ 977,688,000
Number of Days Past Due (Day) | 30 days |
Number of Days of Delinquent Loans Nonaccrual of Interest (Year) | 90 years |
Minimum Number of Days Consumer Loans are Past Due for Losses to be Charged Off (Day) | 120 days |
Maximum Number of Days Consumer Loans are Past Due for Losses to be Charged Off (Day) | 180 days |
Number of Days Loans Secured by Residential Or Commercial Real Estate Are Past Due for Losses to Be Carged Off (Day) | 180 days |
Accrued Interest Receivable, Loans | $ 3,361,000 | 3,298,000
Maximum Loan amount indicated as risk graded | $ 400,000 |
Period of Time Between Issuance of Loan Commitment and Closing and Sale of Loans Lower Range (Day) | 30 days |
Period of Time Between Issuance of Loan Commitments and Closing and Sale of Loans Upper Range (Day) | 60 days |
Goodwill, Impairment Loss | $ 0 | 0
Impairment of intangible assets | $ 0 |
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount (in shares) | 0 |
Advertising Expense | $ 277,000 | 262,000
Segment Reporting, CODM, Profit (Loss) Measure, How Used, Description | The CODM regularly assesses performance of the aggregated single operating and reporting segment and decides how to allocate resources based on net income calculated on the same basis as is net income reported in the Company's consolidated statements of income and other comprehensive income. The CODM is also regularly provided with expense information at a level consistent with that disclosed in the Company's consolidated statements of income and other comprehensive income. |
Segment Reporting, CODM, Individual Title and Position or Group Name [Extensible Enumeration] | srt:ChiefExecutiveOfficerMember |
Acquired Loans |  |
Summary of Significant Accounting Policies [Line Items] |  |
Discount on acquired loans | $ 5,551,000 | $ 7,564,000
Core Deposits [Member] |  |
Summary of Significant Accounting Policies [Line Items] |  |
Estimated useful life | 10 years |
Building [Member] |  |
Summary of Significant Accounting Policies [Line Items] |  |
Property, Plant and Equipment, Useful Life (Year) | 40 years |
Computer Equipment [Member] |  |
Summary of Significant Accounting Policies [Line Items] |  |
Property, Plant and Equipment, Useful Life (Year) | 3 years |
Minimum [Member] |  |
Summary of Significant Accounting Policies [Line Items] |  |
Unallocated Surplus Percent | 0.00% |
Minimum [Member] | Furniture and Fixtures [Member] |  |
Summary of Significant Accounting Policies [Line Items] |  |
Property, Plant and Equipment, Useful Life (Year) | 3 years |
Maximum [Member] |  |
Summary of Significant Accounting Policies [Line Items] |  |
Unallocated Surplus Percent | 5.00% |
Maximum [Member] | Furniture and Fixtures [Member] |  |
Summary of Significant Accounting Policies [Line Items] |  |
Property, Plant and Equipment, Useful Life (Year) | 10 years |

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