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Note 25 - Derivative Instruments - Schedule of Cash Flow Hedging Instruments, Statements of Financial Performance and Financial Position, Location (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Loans, including fees |  | $ 183,560 |  | $ 136,918 |  | $ 89,907
Taxable |  | 19,745 |  | 24,262 |  | 23,260
Total amounts in the Consolidated Statements of Income, Short-term Borrowings |  | 22,584 |  | 20,976 |  | $ 4,339
Designated as Hedging Instrument [Member] |  |  |  |  |  |
Loans, including fees |  | 183,560 |  | 136,918 |  |
Taxable |  | 19,745 |  | 24,262 |  |
Total amounts in the Consolidated Statements of Income, Short-term Borrowings |  | 22,584 |  | 20,976 |  |
Mortgage-backed securities, Notional Amount |  | 200,000 |  | 600,000 |  |
Mortgage-backed securities, Carrying Amount |  | 199,854 |  | 600,339 |  |
Mortgage-backed securities, Fair Value |  | (146) |  | 339 |  |
Designated as Hedging Instrument [Member] | Residential Mortgage-Backed Securities [Member] |  |  |  |  |  |
Mortgage-backed securities, Notional Amount |  | 200,000 | [1] | 200,000 | [2] |
Mortgage-backed securities, Carrying Amount |  | 199,854 | [1] | 200,241 | [2] |
Mortgage-backed securities, Fair Value |  | (146) | [1] | 241 | [2] |
Designated as Hedging Instrument [Member] | Mortgage Loan Pools [Member] |  |  |  |  |  |
Mortgage-backed securities, Notional Amount | [3] |  |  | 400,000 |  |
Mortgage-backed securities, Carrying Amount | [3] |  |  | 400,098 |  |
Mortgage-backed securities, Fair Value | [3] |  |  | 98 |  |
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 |  | 367 |  | 252 |  |
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 |  | 2,280 |  | 1,881 |  |
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 |  |
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 |  |
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 |  |
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 |  | $ 721 |  | $ (473) |  |
[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 September 30, 2024, the amortized cost of the closed portfolios used in these hedging relationships was $313.0 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, 2023, the amortized cost of the closed portfolios used in these hedging relationships was $323.4 million.
[3] | These amounts include the amortized cost basis of residential real estate loans that were used to designate hedging relationships in which the hedged item is the stated amount of assets in the closed portfolio anticipated to be outstanding for the designated hedged period. At December 31, 2023, the amortized cost basis of the residential real estate loans used in these hedging relationships was $687.5 million.

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- Definition Amount of cumulative increase (decrease) in fair value of hedged asset (liabilities) in fair value hedge, attributable to hedged risk. + References No definition available. + Details
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- Definition Amount of increase (decrease) in the fair value of derivatives recognized in the income statement. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4A -Subparagraph (b)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480434/815-10-50-4A + Details
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- Definition Net fair value of all derivative instruments designated as fair value hedging instruments. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 45 -Paragraph 5 -SubTopic 10 -Topic 815 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480463/815-10-45-5 + 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://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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