Note 3 - Securities (Details Textual)	3 Months Ended		6 Months Ended
	Jun. 30, 2024 USD ($)	Jun. 30, 2023 USD ($)	Jun. 30, 2024 USD ($)	Jun. 30, 2023 USD ($)	Dec. 31, 2023 USD ($)
Equity Securities, FV-NI, Current	$ 3,105,000		$ 3,105,000		$ 3,132,000
Equity Securities, FV-NI, Realized Gain (Loss)	0	$ 0	0	$ 0
Equity Securities, FV-NI, Unrealized Gain (Loss)	(24,000)	$ (48,000)	(81,000)	(3,000)
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss	$ 4,704,000,000		4,704,000,000
Number of Debt Securities, Available-for-sale, Sold	17	0
Debt Securities, Available-for-Sale, Book Value of Securities Sold	$ 26,300,000		28,258,000	42,791,000
Debt Securities, Available-for-Sale, Realized Gain	25,000		105,000	215,000
Debt Securities, Available-for-Sale, Realized Loss				72,000
Debt Securities, Available-for-Sale, Realized Gain (Loss)	34,000	$ 0	114,000	143,000
Asset Pledged as Collateral [Member] | Public Funds [Member]
Debt Securities	290,886,000		290,886,000		$ 288,199,000
Debt Securities, Called During The Period [member]
Debt Securities, Realized Gain (Loss)	$ (1,000)	$ 0	$ (9,000)	$ 0