Note 3 - Loans and Allowance for Loan Losses (Details Textual) Pure in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)	Dec. 31, 2021 USD ($)
Mortgage Loans in Process of Foreclosure, Amount	$ 0		$ 0		$ 36,000
Allowance for Loan and Lease Losses, Period Increase (Decrease)			6,600,000		6,100,000
Impaired Financing Receivable, Interest Income, Cash Basis Method		$ 0		$ 0
Financing Receivable, Troubled Debt Restructuring, Commitment to Lend	$ 0		$ 0		0
Financing Receivable, Modifications, Number of Contracts	0	0	0	0
Financing Receivables, Impaired, Troubled Debt Restructuring, Write-down	$ 0	$ 0	$ 0	$ 0
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts	0	0	0
Financing Receivable, Troubled Debt Restructuring, Subsequent Default			$ 280,000	290,000
Provision for Loan and Lease Losses	$ 175,000	$ 0	550,000	75,000
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	$ 294,000		294,000		339,000
Nonaccrual [Member]
Provision for Loan and Lease Losses				$ 7,000
Overall Qualitative Factor [Member]
Allowance for Loan and Lease Losses, Period Increase (Decrease)			6,200,000		5,500,000
Residential Portfolio Segment [Member]
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate, Foreclosure			$ 89,000		$ 53,000

Amount of increase (decrease) of allowance reserve for credit loss.

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The undiscounted sum of all amounts, including amounts deemed principal, interest, fees, penalties, and other under the loan, owed to the investor at the reporting date, whether or not currently due and whether or not any such amounts have been written or charged off by the investor. This relates to loans not accounted for as debt securities, with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

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

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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 financing receivable modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

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

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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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Amount of unfunded portion of contractual agreement to lend funds to borrower for financing receivable modified as troubled debt restructuring.

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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 expense related to estimated loss from loan and lease transactions.

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