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Note 10 - Subordinated Debentures (Details Textual)	1 Months Ended	3 Months Ended	12 Months Ended
	Sep. 30, 2021 USD ($)	Sep. 30, 2021 USD ($)	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2004 USD ($)
Repayments of Debt		$ 2,600,000
Proceeds of Debt Downstreamed		$ 5,000,000.0
Subordinated Debt [Member]
Debt Instrument, Interest Rate, Effective Percentage			2.27%	2.29%
Subordinated Debt [Member] | Subordinated Notes Due 2031 [Member]
Proceeds from Issuance of Subordinated Long-term Debt	$ 32,500,000
Debt Instrument, Interest Rate, Stated Percentage	3.25%	3.25%
Subordinated Debt [Member] | London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument, Basis Spread on Variable Rate			2.05%
Subordinated Debt [Member] | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate [Member] | Subordinated Notes Due 2031 [Member]
Debt Instrument, Basis Spread on Variable Rate	2.55%
Trust Preferred Securities [Member]
Debt Securities, Available-for-sale, Number of Positions Sold					4,500
Debt Securities, Available-for-sale, Price Per Position					1,000

X

- Definition

Number of investments in debt securities measured at fair value which have been sold.

+ References

No definition available.

+ Details

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X

- Definition

Per position price for debt securities classified as available-for-sale.

+ References

No definition available.

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X

- Definition

The amount of cash proceeds from debt that was downstreamed.

+ References

No definition available.

+ Details

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 6
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123466204&loc=SL6036836-161870

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=124435984&loc=d3e28551-108399

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-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
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- Definition

The cash inflow from a borrowing where a lender is placed in a lien position behind debt having a higher priority of repayment (senior) in liquidation of the entity's assets or underlying collateral.

+ References

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-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
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- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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