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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 |

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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 No definition available. + Details
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