Note 8 - Fair Value (Details Textual) - USD ($)	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Jun. 30, 2021	Dec. 31, 2020	Jun. 30, 2020	Dec. 31, 2019
Impaired Loans, Fair Value Disclosure	$ 296,000		$ 296,000			$ 296,000
Impaired Loans, Valuation Allowance	28,000		28,000			28,000
Provision for Loan and Lease Losses, Total	(6,000)	$ (187,000)	(1,019,000)	$ 326,000
Foreclosed Assets, Gross	1,400,000		1,400,000
Foreclosed Assets, Valuation Allowance	336,000	0	336,000	0	$ 281,000	0	$ 0	$ 0
Repossessed Assets, Total	1,049,000	110,000	1,049,000	110,000	$ 1,702,000	$ 157,000	$ 143,000	$ 186,000
Foreclosed Assets Valuation Adjustments	(124,000)	0	(405,000)	(0)
Impaired Loans [Member]
Provision for Loan and Lease Losses, Total	$ 28,000	$ 20,000	$ 28,000	$ 20,000