Note 3 - Investment Securities - Schedule of Investments Classified by Contractual Maturity Date (Details) - USD ($) $ in Thousands	Jun. 30, 2025	Dec. 31, 2024
Due within one year or less, Held-to-maturity, Amortized Cost	$ 6,547
Due within one year or less, Held-to-maturity, Fair Value	6,461
Due within one year or less, Available-for-sale, Amortized Cost	0
Due within one year or less, Available-for-sale, Fair Value	0
Due after one year through five years, Held-to-maturity, Amortized Cost	57,083
Due after one year through five years, Held-to-maturity, Fair Value	53,878
Due after one year through five years, Available-for-sale, Amortized Cost	1,625
Due after one year through five years, Available-for-sale, Fair Value	1,568
Due after five years through ten years, Held-to-maturity, Amortized Cost	43,077
Due after five years through ten years, Held-to-maturity, Fair Value	38,521
Due after five years through ten years, Available-for-sale, Amortized Cost	53,999
Due after five years through ten years, Available-for-sale, Fair Value	50,296
Due after 10 years, Held-to-maturity, Amortized Cost	7,434
Due after 10 years, Held-to-maturity, Fair Value	6,511
Due after 10 years, Available-for-sale, Amortized Cost	349
Due after 10 years, Available-for-sale, Fair Value	349
Held-to-maturity, Amortized cost	114,141
Held-to-maturity, Fair Value	105,371
Available-for-sale, Amortized Cost	55,973
Available-for-sale, Fair Value	52,213
Total investment securities	263,833
Total investment securities, Held-to-maturity, Fair Value	231,504	$ 236,986
Total investment securities, Available-for-sale, Amortized Cost	620,799	686,556
Total investment securities, Available-for-sale, Fair Value	541,152	588,053
Residential Mortgage-Backed Securities [Member]
Residential agency, Held-to-maturity, Amortized Cost	149,692
Residential agency, Held-to-maturity, Fair Value	126,133
Residential agency, Available-for-sale, Amortized Cost	564,826
Residential agency, Available-for-sale, Fair Value	488,939
Total investment securities, Held-to-maturity, Fair Value	126,133	129,001
Total investment securities, Available-for-sale, Fair Value	$ 488,939	$ 503,706