Note 5 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans - Loans Past Due 90 Days or More and Impaired Loans (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2021	Dec. 31, 2020
Loans past due 90 days or more and still accruing		$ 90	$ 17
Ratio of loans past due 90 days or more and still accruing to loans, net of unearned income and deferred fees and costs		0.01%	0.00%
Accruing TDR loans		$ 3,005	$ 1,410
Impaired loans:
Impaired loans with no valuation allowance	[1]	5,878	3,858
Impaired loans with a valuation allowance	[1]	0	1,045
Total impaired loans	[1]	5,878	4,903
Valuation allowance		0	(75)
Impaired loans, net of allowance		5,878	4,828
Average recorded investment in impaired loans(1)	[1]	5,901	5,093
Income recognized on impaired loans, after designation as impaired		$ 137	$ 54

[1] Recorded investment is net of charge-offs and interest paid while a loan is in nonaccrual status.