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Note 8 - Derivatives and Hedging Activities (Details Textual)		3 Months Ended	6 Months Ended	12 Months Ended
	Mar. 15, 2023 USD ($)	Dec. 31, 2022 USD ($)	Jun. 30, 2022 USD ($)	Dec. 31, 2022 USD ($)
Pay Floating Swap Agreement [Member] | Designated as Hedging Instrument [Member] | Cash Flow Hedging [Member]
Derivative, Number of Instruments Held, Total			2
Derivative, Notional Amount			$ 200,000,000.0
Derivative, Fixed Coupon Rate			2.41%
Derivative Instrument, Net cash settlements received		$ 161,000		$ 161,000
Pay Fixed Swap Agreement [Member] | Designated as Hedging Instrument [Member] | Cash Flow Hedging [Member]
Derivative, Number of Instruments Held, Total			1
Derivative, Notional Amount		$ 49,100,000	$ 200,000,000.0	$ 49,100,000
Derivative, Fixed Coupon Rate			2.75%
Derivative, Term of Contract (Year)			8 years	9 years
Pay Fixed Swap Agreement [Member] | Designated as Hedging Instrument [Member] | Cash Flow Hedging [Member] | Subsequent Event [Member]
Derivative, Notional Amount	$ 200,000,000.0
Derivative, Loss on Derivative	$ 4,200,000
Pay Fixed Swap Agreement [Member] | Designated as Hedging Instrument [Member] | Cash Flow Hedging [Member] | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate [Member]
Derivative, Basis Spread on Variable Rate		3.403%		3.403%
Pay Fixed Swap Agreement [Member] | Designated as Hedging Instrument [Member] | Fair Value Hedging [Member]
Derivative, Number of Instruments Held, Total		4		4
Derivative, Notional Amount		$ 201,000,000.0		$ 201,000,000.0
Derivative, Number of Instruments Sold		4		4
Pay Fixed Swap Agreements Expiring in 2032 {Member] | Designated as Hedging Instrument [Member] | Fair Value Hedging [Member]
Derivative, Notional Amount		$ 101,900,000		$ 101,900,000
Derivative, Term of Contract (Year)		10 years
Pay Fixed Swap Agreements Expiring in 2032 {Member] | Designated as Hedging Instrument [Member] | Fair Value Hedging [Member] | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate [Member]
Derivative, Basis Spread on Variable Rate		3.39%		3.39%
The 3.4015 Percent Pay Fixed Swap Agreement [Member] | Designated as Hedging Instrument [Member] | Fair Value Hedging [Member]
Derivative, Notional Amount		$ 50,000,000.0		$ 50,000,000.0
Derivative, Term of Contract (Year)				9 years
The 3.4015 Percent Pay Fixed Swap Agreement [Member] | Designated as Hedging Instrument [Member] | Fair Value Hedging [Member] | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate [Member]
Derivative, Basis Spread on Variable Rate		3.4015%		3.4015%
Four SOFR Cap Agreements [Member]
Derivative, Number of Instruments Held, Total		4	4	4
Derivative, Notional Amount			$ 200,000,000.0
Derivative, Term of Contract (Year)			8 years
Proceeds from Derivative Instrument, Financing Activities		$ 15,550,000
Loss on Derivative Instruments, Pretax		770,803
Four SOFR Cap Agreements [Member] | Not Designated as Hedging Instrument [Member]
Derivative, Notional Amount			$ 16,500,000
Three SOFR Cap Agreement [Member] | Designated as Hedging Instrument [Member] | Fair Value Hedging [Member]
Derivative, Notional Amount			$ 100,000,000.0
Derivative, Floor Interest Rate			2.68%
Three SOFR Cap Agreement [Member] | Designated as Hedging Instrument [Member] | Fair Value Hedging [Member] | Interest Income [Member]
Loss on Derivative Instruments, Pretax		448,900
One SOFR Cap Agreement [Member] | Designated as Hedging Instrument [Member] | Cash Flow Hedging [Member]
Derivative, Floor Interest Rate			2.68%
One SOFR Cap Agreement [Member] | Designated as Hedging Instrument [Member] | Cash Flow Hedging [Member] | Interest Expense [Member]
Loss on Derivative Instruments, Pretax		$ 321,903
One SOFR Cap Agreement [Member] | Not Designated as Hedging Instrument [Member] | Cash Flow Hedging [Member]
Derivative, Notional Amount			$ 100,000,000.0

X

- Definition

Fixed coupon rate related to the derivative.

+ References

No definition available.

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- Definition

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+ References

No definition available.

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- Definition

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+ References

No definition available.

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- Definition

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+ References

No definition available.

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- Definition

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+ References

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- Definition

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
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The number of derivative instruments of a particular group held by the entity.

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- Definition

Period the derivative contract is outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

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+ References

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Section 45
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