Note 6 - Loans and Allowance for Credit Losses on Loans - Financing Receivable, Troubled Debt Restructuring (Details) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)
Number of Contracts	1	0	8	0
Pre-modification Recorded Investment	$ 41	$ 0	$ 509	$ 0
Post-modification Recorded Investment	$ 41	$ 0	$ 509	$ 0
Residential 1-4 Family Real Estate, Personal Residence [Member]
Number of Contracts	1	0	7	0
Pre-modification Recorded Investment	$ 41	$ 0	$ 377	$ 0
Post-modification Recorded Investment	$ 41	$ 0	$ 377	$ 0
Home Equity Loan [Member]
Number of Contracts			1	0
Pre-modification Recorded Investment			$ 132	$ 0
Post-modification Recorded Investment			$ 132	$ 0

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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI https://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524

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Amount, after troubled debt restructuring, of modified financing receivable.

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Amount, before troubled debt restructuring, of financing receivable to be modified.

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