Note 2 - INVESTMENT SECURITIES - Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Securities HTM:
Securities held to maturity, due in one year or less, amortized cost	$ 1,702
Securities held to maturity, due in one year or less, fair value	1,691
Securities held to maturity, due after one year through five years, amortized cost	23,792
Securities held to maturity, due after one year through five years, fair value	24,783
Securities held to maturity, due after five years, amortized cost	693,332
Securities held to maturity, due after five years, fair value	669,696
Securities HTM, Amortized cost	718,826	$ 683,707
Securities held to maturity, fair value	696,170	680,279
Securities AFS:
Securities available for sale, due in one year or less, amortized cost	919
Securities available for sale, Due in one year or less, fair value	914
Securities available for sale, due after one year through five years, amortized cost	17,054
Securities available for sale, Due after one year through five years, fair value	16,069
Securities available for sale, due after five years, amortized cost	248,244
Securities available for sale, due after five years, fair value	203,641
Securities available for sale, single maturity, amortized cost	266,217
Securities available for sale, single maturity, fair value	220,624
Securities AFS, Amortized Cost	342,660	348,633
Available-for-sale Securities, Debt Securities, Total	290,980	299,655
Callable Securities [Member]
Securities AFS:
Securities AFS, Amortized Cost	247,143
Available-for-sale Securities, Debt Securities, Total	204,166
Municipal securities.
Securities HTM:
Securities HTM, Amortized cost	717,776	682,657
Securities held to maturity, fair value	695,135	679,201
Securities AFS:
Securities AFS, Amortized Cost	205,928	206,566
Available-for-sale Securities, Debt Securities, Total	166,693	170,987
Municipal securities. | Callable Securities [Member]
Securities HTM:
Securities held to maturity, callable, amortized cost	284,307
Securities held to maturity, callable, fair value	276,852
Securities AFS:
Securities available for sale, callable, amortized cost	204,865
Securities available for sale, callable, fair value	165,649
Asset-backed securities
Securities AFS:
Securities AFS, Amortized Cost	14,093	15,261
Available-for-sale Securities, Debt Securities, Total	14,285	15,423
Securities available for sale, callable, amortized cost	14,093
Securities available for sale, callable, fair value	14,285
Residential mortgage-backed and related securities
Securities AFS:
Securities AFS, Amortized Cost	62,350	65,168
Available-for-sale Securities, Debt Securities, Total	56,071	59,196
Securities available for sale, callable, amortized cost	62,350
Securities available for sale, callable, fair value	56,071
Other securities
Securities HTM:
Securities HTM, Amortized cost		1,050
Securities held to maturity, fair value	1,035	1,078
Securities AFS:
Securities AFS, Amortized Cost	43,235	44,239
Available-for-sale Securities, Debt Securities, Total	39,489	$ 39,076
Other securities | Callable Securities [Member]
Securities AFS:
Securities available for sale, callable, amortized cost	42,278
Securities available for sale, callable, fair value	$ 38,517