Note 6 - Securities Available for Sale - Securities in a Continuous Unrealized Loss Position (Details) Pure in Thousands, $ in Thousands	Mar. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
Less Than Twelve Months # of Investments	5	1
Less Than Twelve Months Fair Value	$ 24,874	$ 5,000
Less Than Twelve Months Unrealized Losses	$ (76)	$ (9)
Twelve Months or More # of Investments	63	66
Twelve Months or More Fair Value	$ 172,438	$ 195,870
Twelve Months or More Unrealized Losses	(18,346)	(18,495)
Total fair value	197,312	200,870
Total temporarily impaired securities	$ (18,422)	$ (18,504)
Mortgage Backed Securities, Issued by Us Government Sponsored Enterprises, Federal National Mortgage Association Certificates and Obligations FNMA [Member]
Less Than Twelve Months # of Investments	0	0
Less Than Twelve Months Fair Value	$ 0	$ 0
Less Than Twelve Months Unrealized Losses	$ 0	$ 0
Twelve Months or More # of Investments	34	34
Twelve Months or More Fair Value	$ 82,474	$ 87,133
Twelve Months or More Unrealized Losses	(9,625)	(9,704)
Total fair value	82,474	87,133
Total temporarily impaired securities	$ (9,625)	$ (9,704)
Mortgage Backed Securities, Issued by Us Government Sponsored Enterprises, Federal Home Loan Mortgage Corporation Certificates and Obligations FHLMC [Member]
Less Than Twelve Months # of Investments	0	0
Less Than Twelve Months Fair Value	$ 0	$ 0
Less Than Twelve Months Unrealized Losses	$ 0	$ 0
Twelve Months or More # of Investments	24	24
Twelve Months or More Fair Value	$ 70,254	$ 74,249
Twelve Months or More Unrealized Losses	(8,398)	(8,246)
Total fair value	70,254	74,249
Total temporarily impaired securities	$ (8,398)	$ (8,246)
Mortgage Backed Securities, Federal National Mortgage Association Certificates and Obligations FNMA [Member]
Less Than Twelve Months # of Investments	0	0
Less Than Twelve Months Fair Value	$ 0	$ 0
Less Than Twelve Months Unrealized Losses	$ 0	$ 0
Twelve Months or More # of Investments	1	1
Twelve Months or More Fair Value	$ 31	$ 32
Twelve Months or More Unrealized Losses	(2)	(2)
Total fair value	31	32
Total temporarily impaired securities	$ (2)	$ (2)
Other Marketable Securities, Us Government Agencies Debt Securities [Member]
Less Than Twelve Months # of Investments	5	1
Less Than Twelve Months Fair Value	$ 24,874	$ 5,000
Less Than Twelve Months Unrealized Losses	$ (76)	$ (9)
Twelve Months or More # of Investments	4	7
Twelve Months or More Fair Value	$ 19,679	$ 34,456
Twelve Months or More Unrealized Losses	(321)	(543)
Total fair value	44,553	39,456
Total temporarily impaired securities	$ (397)	$ (552)