Note 7 - Deposits (Details Textual) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Time Deposits, at or Above FDIC Insurance Limit	$ 21.1	$ 23.0
Overdraft Deposits Reclassified as Loan Balances	0.3	$ 0.6
Asset Pledged as Collateral [Member] \| Deposits and Trust Funds [Member]
Investments, Fair Value Disclosure, Total	608.1
Asset Pledged as Collateral [Member] \| Deposits [Member]
Deposit Liabilities, Collateral Issued, Financial Instruments	510.9
Asset Pledged as Collateral [Member] \| Other Pledging Needs [Member]
Investments, Fair Value Disclosure, Total	$ 97.2

Amount of overdraft deposits that are reclassified as loan balances.

No definition available.

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Balance Type:	credit
Period Type:	instant

- Definition

Amount of securities, mortgage loans, or other financial instruments pledged as collateral for deposits.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 405
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=116652737&loc=d3e64164-112818

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258

+ Details

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- Definition

Amount of time deposit liabilities, including certificates of deposit, in denominations that meet or exceed the Federal Deposit Insurance Corporation (FDIC) insurance limit.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 405
-Section 50
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=116652737&loc=d3e64164-112818

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- Details

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Balance Type:
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- Details

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- Details

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