Note 9 - Fair Value Measurement - Assets and Liabilities Measured at Fair Value on a Non-recurring Basis (Details) - Fair Value, Nonrecurring [Member] - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2024	Dec. 31, 2023
Commercial Loans [Member]
Commercial	$ 27	$ 27
Fair value adjustment	0	271
Commercial Loans [Member] | Fair Value, Inputs, Level 1 [Member]
Commercial	0	0
Commercial Loans [Member] | Fair Value, Inputs, Level 2 [Member]
Commercial	0	0
Commercial Loans [Member] | Fair Value, Inputs, Level 3 [Member]
Commercial	27	27
Real Estate Loan [Member]
RE – Residential	0	0
Real Estate Loan [Member] | Residential Portfolio Segment [Member]
RE – Residential	357	357
Real Estate Loan [Member] | Fair Value, Inputs, Level 1 [Member]
RE – Residential	0	0
Real Estate Loan [Member] | Fair Value, Inputs, Level 2 [Member]
RE – Residential	0	0
Real Estate Loan [Member] | Fair Value, Inputs, Level 3 [Member]
RE – Residential	$ 357	$ 357