Reflects the amount of the write-down related to a troubled debt restructuring.

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Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
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Amortized cost excluding accrued interest, after allowance for credit loss, of financing receivable. Excludes net investment in lease.

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Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
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Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

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Amount of interest income on financing receivable on nonaccrual status.

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Amortized cost of financing receivable on nonaccrual status. Excludes net investment in lease.

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Amount of interest income recognized on a cash-basis method of accounting that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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- Definition

Amount of commitment to lend additional funds to debtor experiencing financial difficulty for which creditor has modified terms of financing receivable.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

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Amount of decrease in investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate, from foreclosure.

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Amount of expected credit loss for credit exposure on off-balance-sheet commitment, including but not limited to, loan commitment, standby letter of credit, financial guarantee not accounted for as insurance. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

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Amount of expense (reversal of expense) for expected credit loss for off-balance sheet credit exposure. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

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Note 4 - Loans and Allowance for Loan Losses (Details Textual) Pure in Thousands		3 Months Ended		12 Months Ended
	Mar. 31, 2023 USD ($)	Mar. 31, 2023 USD ($)	Mar. 31, 2022 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2021 USD ($)
Mortgage Loans in Process of Foreclosure, Amount	$ 0	$ 0
Interest Receivable	4,156,000	4,156,000		$ 4,285,000
Financing Receivable, Nonaccrual	1,260,000	1,260,000
Financing Receivable, Nonaccrual, Interest Income		0
Financing Receivable, Troubled Debt Restructuring, Commitment to Lend	0	0		0
Financing Receivable, Modifications, Number of Contracts			0
Financing Receivables, Troubled Debt Restructuring, Write-down			$ 0
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts			0
Impaired Financing Receivable, Interest Income, Cash Basis Method			$ 0
Financing Receivable, Excluding Accrued Interest, after Allowance for Credit Loss	565,576,000	565,576,000		557,958,000
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest	7,323,000	7,323,000	6,245,000	6,772,000	$ 6,772,000	$ 6,083,000
Unfunded Loan Commitment [Member]
Off-Balance-Sheet, Credit Loss, Liability	131,000	131,000
Off-Balance-Sheet, Credit Loss, Liability, Credit Loss Expense (Reversal)		0
Financial Asset Acquired with Credit Deterioration [Member]
Financing Receivable, Excluding Accrued Interest, after Allowance for Credit Loss	242,000	242,000		244,000
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest	0	0	$ 31,000	0	$ 0
Accrued Interest Receivable [Member]
Interest Receivable	1,900,000	$ 1,900,000
Residential Real Estate [Member]
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate, Foreclosure				$ 104,000
Residential Portfolio Segment [Member]
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate, Foreclosure	$ 382,000