Note 10 - Federal Income Taxes - Significant Components of Deferred Tax Assets and Liabilities (Details) - USD ($)	Dec. 31, 2021	Dec. 31, 2020
Allowance for loan losses	$ 7,426,000	$ 7,973,000
Deferred compensation	259,000	511,000
Stock compensation	941,000	541,000
Nonaccrual loan interest income	159,000	211,000
Deferred loan fees	520,000	924,000
Unrealized loss on securities	991,000	0
Fair value write-downs on foreclosed properties	0	537,000
Other	1,344,000	938,000
Deferred tax asset	11,640,000	11,635,000
Depreciation	1,168,000	1,175,000
Prepaid expenses	416,000	297,000
Core deposit intangible	276,000	498,000
Mortgage loan servicing rights	2,572,000	1,720,000
Unrealized gain on securities	0	1,458,000
Business combination adjustments	2,013,000	2,142,000
Other	942,000	521,000
Deferred tax liability	7,387,000	7,811,000
Total net deferred tax asset	$ 4,253,000	$ 3,824,000