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Note 10 - Borrowed Funds (Details Textual) - USD ($) $ in Thousands			12 Months Ended
	Dec. 14, 2023	May 12, 2023	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Federal Home Loan Bank, Advance, Maturity, Year One			$ 0
Proceeds from Short-Term Debt			(333,000)	$ 0	$ 0
Residential Mortgage Segment [Member]
Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Collateral Pledged			43,100
US Treasury Securities [Member]
Investment Owned, Face Amount			35,000
Federal Reserve Bank Advances [Member]
Short-Term Debt			21,500	0
Proceeds from Short-Term Debt	$ 21,500	$ 13,000		$ 0	$ 0
Debt Instrument, Interest Rate, Stated Percentage	4.89%	4.99%
Debt Instrument, Term (Year)	1 year	1 year
Federal Reserve Bank Advances [Member] \| Asset Pledged as Collateral [Member]
Investment Owned, Balance, Principal Amount			48,900
Investment Owned, Fair Value			$ 45,900