Note 8 - Deposits (Details) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Aggregate amount of certificates of deposits, $250,000 minimum denomination	$ 169,000,000.0	$ 175,600,000
Minimum denomination	250,000
Prepaid brokered and public time deposits		29,200,000
Loss on prepayment of brokered and public time deposits		576,000
Prepayment of brokered certificate of deposits	0
Federal Home Loan Bank of Des Moines [Member]
FHLB advance	129,500,000	110,500,000
Amount outstanding	$ 0	$ 0