Note 3 - Loans and Allowance for Credit Losses - Loans Modified as Troubled Debt Restructurings (Details)	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022 USD ($)
Financing Receivable, Modified, Number of Contracts	0	2
Pre- Modification Recorded Principal Balance		$ 128,000
Post- Modification Recorded Principal Balance		$ 128,000
Commercial Portfolio Segment [Member]
Financing Receivable, Modified, Number of Contracts		0
Pre- Modification Recorded Principal Balance		$ 0
Post- Modification Recorded Principal Balance		$ 0
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member]
Financing Receivable, Modified, Number of Contracts		0
Pre- Modification Recorded Principal Balance		$ 0
Post- Modification Recorded Principal Balance		$ 0
Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member]
Financing Receivable, Modified, Number of Contracts		0
Pre- Modification Recorded Principal Balance		$ 0
Post- Modification Recorded Principal Balance		$ 0
Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member]
Financing Receivable, Modified, Number of Contracts		0
Pre- Modification Recorded Principal Balance		$ 0
Post- Modification Recorded Principal Balance		$ 0
Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member]
Financing Receivable, Modified, Number of Contracts		0
Pre- Modification Recorded Principal Balance		$ 0
Post- Modification Recorded Principal Balance		$ 0
Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member]
Financing Receivable, Modified, Number of Contracts		0
Pre- Modification Recorded Principal Balance		$ 0
Post- Modification Recorded Principal Balance		$ 0
Retail Portfolio Segment [Member]
Financing Receivable, Modified, Number of Contracts		2
Pre- Modification Recorded Principal Balance		$ 128,000
Post- Modification Recorded Principal Balance		$ 128,000
Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member]
Financing Receivable, Modified, Number of Contracts		2
Pre- Modification Recorded Principal Balance		$ 128,000
Post- Modification Recorded Principal Balance		$ 128,000
Retail Portfolio Segment [Member] | Other Consumer Loans [Member]
Financing Receivable, Modified, Number of Contracts		0
Pre- Modification Recorded Principal Balance		$ 0
Post- Modification Recorded Principal Balance		$ 0