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Note 8 - Deposits and Borrowed Funds (Details Textual) - USD ($) | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024 | Dec. 31, 2024
Demand Deposit Overdrafts | $ 490,000 |  | $ 490,000 |  | $ 591,000
Interest Expense, Time Deposits, $100,000 or More | 12,000 | $ 30,000 | 43,000 | $ 71,000 |
Short-term Line of Credit | 0 |  | 0 |  |
Federal Reserve [Member] |  |  |  |  |
Line of Credit Facility, Maximum Borrowing Capacity | 647,776,000 |  | 647,776,000 |  |
Short-term Line of Credit | 0 |  | 0 |  |
Federal Reserve [Member] | Assets Available to be Pledged as Collateral [Member] |  |  |  |  |
Debt Securities, Available-for-Sale and Held-to-Maturity, after Allowance for Credit Loss | 1,970,022 |  | 1,970,022 |  |
Corresponding Banks [Member] |  |  |  |  |
Line of Credit Facility, Maximum Borrowing Capacity | $ 60,000,000 |  | $ 60,000,000 |  |

X
- Definition Amount, after allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity) and investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481830/320-10-45-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 942 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(6)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1 + Details
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- Definition Interest expense incurred on time deposits, including certificates of deposits, of $100,000 or more in domestic offices. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 942 -SubTopic 220 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04(6)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478524/942-220-S99-1 + Details
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X
- Definition Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)(b)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(19)(b)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 + Details
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X
- Definition Amounts honored in excess of customers account balances, recorded by the bank as a loan. + References No definition available. + Details
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X
- Definition The amount of short-term line of credit outstanding. + References No definition available. + Details
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