Note 4 - Loans and the Allowance for Loan Losses - Impaired Loans (Details) $ in Thousands	12 Months Ended
Dec. 31, 2022 USD ($)
Related Allowance	$ 20
Recorded investment	1,248
Unpaid principal balance	1,337
Average recorded investment	1,271
Interest income recognized	59
Commercial Portfolio Segment [Member] \| Commercial Loans [Member]
Recorded investment with no related allowance recorded	0
Unpaid principal balance with no related allowance recorded	0
Average recorded investment with no related allowance recorded	0
Interest income recognized with no related allowance recorded	0
Recorded investment with an allowance	0
Unpaid principal balance with allowance	0
Related Allowance	0
Average recorded investment with an allowance	0
Interest income recognized with an allowance	0
Recorded investment	0
Unpaid principal balance	0
Average recorded investment	0
Interest income recognized	0
Commercial Portfolio Segment [Member] \| Agricultural Loans [Member]
Recorded investment with no related allowance recorded	232
Unpaid principal balance with no related allowance recorded	232
Average recorded investment with no related allowance recorded	235
Interest income recognized with no related allowance recorded	17
Recorded investment with an allowance	0
Unpaid principal balance with allowance	0
Related Allowance	0
Average recorded investment with an allowance	0
Interest income recognized with an allowance	0
Recorded investment	232
Unpaid principal balance	232
Average recorded investment	235
Interest income recognized	17
Commercial Portfolio Segment [Member] \| Real Estate Loan [Member]
Recorded investment with no related allowance recorded	0
Unpaid principal balance with no related allowance recorded	0
Average recorded investment with no related allowance recorded	0
Interest income recognized with no related allowance recorded	0
Recorded investment with an allowance	0
Unpaid principal balance with allowance	0
Related Allowance	0
Average recorded investment with an allowance	0
Interest income recognized with an allowance	0
Recorded investment	0
Unpaid principal balance	0
Average recorded investment	0
Interest income recognized	0
Commercial Portfolio Segment [Member] \| Construction Loans [Member]
Recorded investment with no related allowance recorded	94
Unpaid principal balance with no related allowance recorded	94
Average recorded investment with no related allowance recorded	98
Interest income recognized with no related allowance recorded	6
Recorded investment with an allowance	0
Unpaid principal balance with allowance	0
Related Allowance	0
Average recorded investment with an allowance	0
Interest income recognized with an allowance	0
Recorded investment	94
Unpaid principal balance	94
Average recorded investment	98
Interest income recognized	6
Residential Portfolio Segment [Member] \| Real Estate Loan [Member]
Recorded investment with no related allowance recorded	509
Unpaid principal balance with no related allowance recorded	541
Average recorded investment with no related allowance recorded	514
Interest income recognized with no related allowance recorded	29
Recorded investment with an allowance	169
Unpaid principal balance with allowance	169
Related Allowance	20
Average recorded investment with an allowance	170
Interest income recognized with an allowance	7
Recorded investment	678
Unpaid principal balance	710
Average recorded investment	684
Interest income recognized	36
Residential Portfolio Segment [Member] \| Equity Lines of Credit [Member]
Recorded investment with no related allowance recorded	244
Unpaid principal balance with no related allowance recorded	301
Average recorded investment with no related allowance recorded	254
Interest income recognized with no related allowance recorded	0
Recorded investment with an allowance	0
Unpaid principal balance with allowance	0
Related Allowance	0
Average recorded investment with an allowance	0
Interest income recognized with an allowance	0
Recorded investment	244
Unpaid principal balance	301
Average recorded investment	254
Interest income recognized	0
Consumer Portfolio Segment [Member] \| Automobile Loan [Member]
Recorded investment with no related allowance recorded	0
Unpaid principal balance with no related allowance recorded	0
Average recorded investment with no related allowance recorded	0
Interest income recognized with no related allowance recorded	0
Recorded investment with an allowance	0
Unpaid principal balance with allowance	0
Related Allowance	0
Average recorded investment with an allowance	0
Interest income recognized with an allowance	0
Recorded investment	0
Unpaid principal balance	0
Average recorded investment	0
Interest income recognized	0
Consumer Portfolio Segment [Member] \| Other Loans [Member]
Recorded investment with no related allowance recorded	0
Unpaid principal balance with no related allowance recorded	0
Average recorded investment with no related allowance recorded	0
Interest income recognized with no related allowance recorded	0
Recorded investment with an allowance	0
Unpaid principal balance with allowance	0
Related Allowance	0
Average recorded investment with an allowance	0
Interest income recognized with an allowance	0
Recorded investment	0
Unpaid principal balance	0
Average recorded investment	0
Interest income recognized	$ 0

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

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