Note 5 - Fair Value Measurements - Estimated Fair Value of the Company's Financial Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Reported Value Measurement [Member]
Financial assets:
Cash and cash equivalents	$ 132,351	$ 112,417
Loans held for sale	676	878
Net loans	996,048	1,090,626
Bank-owned life insurance	16,954	16,938
Federal Home Loan Bank stock	4,399	5,057
Accrued interest receivable	4,392	5,210
Financial liabilities:
Deposits	1,200,557	1,225,200
Other borrowings	12,966	17,038
Accrued interest payable	305	580
Estimate of Fair Value Measurement [Member]
Financial assets:
Cash and cash equivalents	132,351	112,417
Loans held for sale	1,105	878
Net loans	986,527	1,089,573
Bank-owned life insurance	16,954	16,938
Federal Home Loan Bank stock	4,399	5,057
Accrued interest receivable	4,392	5,210
Financial liabilities:
Deposits	1,202,362	1,229,101
Other borrowings	12,966	15,250
Accrued interest payable	305	580
Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 1 [Member]
Financial assets:
Cash and cash equivalents	132,351	112,417
Loans held for sale	0	0
Net loans	0	0
Bank-owned life insurance	16,954	16,938
Federal Home Loan Bank stock	4,399	5,057
Accrued interest receivable	4,392	5,210
Financial liabilities:
Deposits	988,883	929,450
Other borrowings	0	0
Accrued interest payable	305	580
Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 2 [Member]
Financial assets:
Cash and cash equivalents	0	0
Loans held for sale	1,105	878
Net loans	0	0
Bank-owned life insurance	0	0
Federal Home Loan Bank stock	0	0
Accrued interest receivable	0	0
Financial liabilities:
Deposits	0	0
Other borrowings	0	0
Accrued interest payable	0	0
Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 3 [Member]
Financial assets:
Cash and cash equivalents	0	0
Loans held for sale	0	0
Net loans	986,527	1,089,573
Bank-owned life insurance	0	0
Federal Home Loan Bank stock	0	0
Accrued interest receivable	0	0
Financial liabilities:
Deposits	213,479	299,651
Other borrowings	12,966	15,250
Accrued interest payable	$ 0	$ 0