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Note 18 - Derivative Instruments - Schedule of Cash Flow Hedging Instruments, Statements of Financial Performance and Financial Position, Location (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024 | Dec. 31, 2024
Loans, including fees | $ 63,875 |  | $ 42,593 | $ 189,222 |  | $ 123,551 |  |
Taxable | 5,091 |  | 4,596 | 16,108 |  | 14,008 |  |
Total amounts in the Consolidated Statements of Income, Short-term Borrowings | 2,506 |  | 6,706 | 9,327 |  | 19,748 |  |
Designated as Hedging Instrument [Member] |  |  |  |  |  |  |  |
Loans, including fees | 63,875 |  | 42,593 | 189,222 |  | 123,551 |  |
Taxable | 5,091 |  | 4,596 | 16,108 |  | 14,008 |  |
Total amounts in the Consolidated Statements of Income, Short-term Borrowings | 2,506 |  | 6,706 | 9,327 |  | 19,748 |  |
Mortgage-backed securities, Notional Amount | 200,000 |  |  | 200,000 |  |  | $ 200,000 |
Mortgage-backed securities, Carrying Amount | 200,100 |  |  | 200,100 |  |  | 199,854 |
Mortgage-backed securities, Fair Value |  |  |  | 100 |  |  | (146) |
Designated as Hedging Instrument [Member] | Residential Mortgage-Backed Securities [Member] |  |  |  |  |  |  |  |
Mortgage-backed securities, Notional Amount | 200,000 | [1] |  | 200,000 | [1] |  | 200,000 | [2]
Mortgage-backed securities, Carrying Amount | 200,100 | [1] |  | 200,100 | [1] |  | 199,854 | [2]
Mortgage-backed securities, Fair Value |  |  |  | 100 | [1] |  | $ (146) | [2]
Designated as Hedging Instrument [Member] | Interest Rate Swap [Member] | Fair Value Hedging [Member] | Interest and Fee Income, Loans and Leases [Member] |  |  |  |  |  |  |  |
Derivative, Gain (Loss) on Derivative, Net | 0 |  | 46 | 0 |  | 367 |  |
Designated as Hedging Instrument [Member] | Interest Rate Swap [Member] | Fair Value Hedging [Member] | Interest Income, Securities, Operating, Taxable [Member] |  |  |  |  |  |  |  |
Derivative, Gain (Loss) on Derivative, Net | 150 |  | 653 | 441 |  | 1,954 |  |
Designated as Hedging Instrument [Member] | Interest Rate Swap [Member] | Fair Value Hedging [Member] | Interest Expense, Short-Term Borrowings [Member] |  |  |  |  |  |  |  |
Derivative, Gain (Loss) on Derivative, Net | 0 |  | 0 | 0 |  | 0 |  |
Designated as Hedging Instrument [Member] | Interest Rate Swap [Member] | Cash Flow Hedging [Member] | Interest and Fee Income, Loans and Leases [Member] |  |  |  |  |  |  |  |
Derivative, Gain (Loss) on Derivative, Net | 0 |  | 0 | 0 |  | 0 |  |
Designated as Hedging Instrument [Member] | Interest Rate Swap [Member] | Cash Flow Hedging [Member] | Interest Income, Securities, Operating, Taxable [Member] |  |  |  |  |  |  |  |
Derivative, Gain (Loss) on Derivative, Net | 0 |  | 0 | 0 |  | 0 |  |
Designated as Hedging Instrument [Member] | Interest Rate Swap [Member] | Cash Flow Hedging [Member] | Interest Expense, Short-Term Borrowings [Member] |  |  |  |  |  |  |  |
Derivative, Gain (Loss) on Derivative, Net | $ 0 |  | $ (253) | $ 721 |  | $ (785) |  |
[1] | Includes amounts related to residential agency mortgage-backed securities currently designated as the hedged item in a fair value hedge using the portfolio layer method. At June 30, 2025, the amortized cost of the closed portfolios used in these hedging relationships was $281.6 million.
[2] | Includes amounts related to residential agency mortgage-backed securities currently designated as the hedged item in a fair value hedge using the portfolio layer method. At December 31, 2024, the amortized cost of the closed portfolios used in these hedging relationships was $296.9 million.

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- Definition Net fair value of all derivative instruments designated as fair value hedging instruments. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4B -Subparagraph (c)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480434/815-10-50-4B + Details
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- Definition The aggregate interest and fee income generated by: (1) loans the Entity has positive intent and ability to hold for the foreseeable future, or until maturity or payoff, including commercial and consumer loans, whether domestic or foreign, which may consist of: (a) industrial and agricultural; (b) real estate; and (c) real estate construction loans; (d) trade financing; (e) lease financing; (f) home equity lines-of-credit; (g) automobile and other vehicle loans; and (h) credit card and other revolving-type loans and (2) loans and leases held-for-sale which may include mortgage loans, direct financing, and sales-type leases. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 220 -SubTopic 40 -Name Accounting Standards Codification -Section 55 -Paragraph 21 -Publisher FASB -URI https://asc.fasb.org/1943274/2147476153/220-40-55-21 Reference 2: 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(1)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478524/942-220-S99-1 + Details
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