Note 9 - Short-Term Borrowings (Details Textual)	Dec. 31, 2021 USD ($) FederalFund	Dec. 31, 2020 USD ($)
Short-term Borrowings [Line Items]
Available-for-sale Securities Pledged as Collateral	$ 264,154,000	$ 220,934,000
Federal Funds Unsecured Number of Lines \| FederalFund	5
Federal Funds Unsecured Lines	$ 101,000,000
Federal Funds Purchased	0	0
Securities Sold under Agreements to Repurchase [Member]
Short-term Borrowings [Line Items]
Available for Sale Securities Pledged as Collateral Amortized Cost	89,439,000	69,793,000
Available-for-sale Securities Pledged as Collateral	$ 89,361,000	$ 71,295,000

The amortized cost of available-for-sale securities that serve as collateral for borrowings.

No definition available.

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- Definition

Amount of Federal Funds lines granted by correspondent banks.

+ References

No definition available.

+ Details

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- Definition

The number of Federal Fund lines granted by correspondent banks.

+ References

No definition available.

+ Details

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- Definition

Amount of restricted 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/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 954
-SubTopic 210
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=120413173&loc=SL6242262-115580

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 1A
-Subparagraph (b)(1)(i)
-URI http://asc.fasb.org/extlink&oid=109249958&loc=SL6224234-111729

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 954
-SubTopic 210
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=120413209&loc=SL6242269-115581

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- Definition

Amount of short term borrowing where a bank borrows, at the federal funds rate, from another bank.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.13(1))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Details

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