Note 7 - Deposits and Borrowed Funds (Details Textual) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Demand Deposit Overdrafts	$ 620	$ 995
Interest Expense, Time Deposits, $100,000 or More	116	$ 156	$ 265
Corresponding Banks [Member]
Line of Credit Facility, Maximum Borrowing Capacity	100,000
Proceeds from Lines of Credit	0
Line of Credit Facility, Average Outstanding Amount	0
Federal Reserve [Member]
Line of Credit Facility, Maximum Borrowing Capacity	996,935
Federal Reserve [Member] \| Assets Available To Be Pledged As Collateral [Member]
Available for Sale and Held to Maturity Debt Securities	$ 1,945,176

Interest expense incurred on time deposits, including certificates of deposits, of $100,000 or more in domestic offices.

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//1943274/2147483589/942-220-S99-1

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- Definition

Average amount borrowed under the credit facility during the period.

+ References

No definition available.

+ Details

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- 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
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-Publisher FASB
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- Definition

Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(f))
-Publisher FASB
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
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-Section 45
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-Publisher FASB
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The amount of available for sale and held to maturity debt securities.

+ References

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- Definition

Amounts honored in excess of customers account balances, recorded by the bank as a loan.

+ References

No definition available.

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