Note 11 - Fair Value of Financial Instruments - Estimated Fair Value and Carrying Amounts of Financial Instruments (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Estimate of Fair Value Measurement [Member]
Cash and cash equivalents	$ 22,994	$ 21,811
FHLB stock	10,099	5,089
FRB stock	4,131	4,131
Loans receivable, gross	1,362,776	1,322,814
Accrued interest and dividends receivable	11,194	11,284
Mortgage servicing rights	20,199	19,288
Non-maturing interest-bearing deposits	790,367	914,659
Noninterest-bearing deposits	432,463	468,955
Time certificates of deposit	351,199	246,348
Accrued expenses and other liabilities	31,945	26,377
FHLB advances and other borrowings	191,107	69,373
Other long-term debt	56,864	56,721
Reported Value Measurement [Member]
Cash and cash equivalents	22,994	21,811
FHLB stock	10,099	5,089
FRB stock	4,131	4,131
Loans receivable, gross	1,421,483	1,353,678
Accrued interest and dividends receivable	11,194	11,284
Mortgage servicing rights	15,501	15,412
Non-maturing interest-bearing deposits	790,367	914,659
Noninterest-bearing deposits	432,463	468,955
Time certificates of deposit	355,537	251,658
Accrued expenses and other liabilities	31,945	26,377
FHLB advances and other borrowings	191,260	69,394
Other long-term debt	60,155	60,155
Fair Value, Inputs, Level 1 [Member] | Estimate of Fair Value Measurement [Member]
Cash and cash equivalents	22,994	21,811
FHLB stock	0	0
FRB stock	0	0
Loans receivable, gross	0	0
Accrued interest and dividends receivable	11,194	11,284
Mortgage servicing rights	0	0
Non-maturing interest-bearing deposits	0	0
Noninterest-bearing deposits	432,463	468,955
Time certificates of deposit	0	0
Accrued expenses and other liabilities	31,945	26,377
FHLB advances and other borrowings	0	0
Other long-term debt	0	0
Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value Measurement [Member]
Cash and cash equivalents	0	0
FHLB stock	10,099	5,089
FRB stock	4,131	4,131
Loans receivable, gross	0	0
Accrued interest and dividends receivable	0	0
Mortgage servicing rights	0	0
Non-maturing interest-bearing deposits	790,367	914,659
Noninterest-bearing deposits	0	0
Time certificates of deposit	0	0
Accrued expenses and other liabilities	0	0
FHLB advances and other borrowings	0	0
Other long-term debt	0	0
Fair Value, Inputs, Level 3 [Member] | Estimate of Fair Value Measurement [Member]
Cash and cash equivalents	0	0
FHLB stock	0	0
FRB stock	0	0
Loans receivable, gross	1,362,776	1,322,814
Accrued interest and dividends receivable	0	0
Mortgage servicing rights	20,199	19,288
Non-maturing interest-bearing deposits	0	0
Noninterest-bearing deposits	0	0
Time certificates of deposit	351,199	246,348
Accrued expenses and other liabilities	0	0
FHLB advances and other borrowings	191,107	69,373
Other long-term debt	$ 56,864	$ 56,721