Note 2 - INVESTMENT SECURITIES - Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Securities HTM:
Securities held to maturity, due in one year or less, amortized cost	$ 9,064
Securities held to maturity, due in one year or less, fair value	9,149
Securities held to maturity, due after one year through five years, amortized cost	32,996
Securities held to maturity, due after one year through five years, fair value	35,709
Securities held to maturity, due after five years, amortized cost	520,089
Securities held to maturity, due after five years, fair value	484,108
Securities HTM, Amortized cost	562,149	$ 587,322
Securities held to maturity, fair value	528,966	535,636
Securities AFS:
Securities available for sale, due in one year or less, amortized cost	6,561
Securities available for sale, Due in one year or less, fair value	6,556
Securities available for sale, due after one year through five years, amortized cost	2,500
Securities available for sale, Due after one year through five years, fair value	2,468
Securities available for sale, due after five years, amortized cost	271,073
Securities available for sale, due after five years, fair value	225,382
Securities available for sale, single maturity, amortized cost	280,134
Securities available for sale, single maturity, fair value	234,406
Securities AFS, Amortized Cost	367,636	400,511
Available-for-sale Securities, Debt Securities, Total	315,477	340,960
Callable Securities [Member]
Securities AFS:
Securities AFS, Amortized Cost	254,564
Available-for-sale Securities, Debt Securities, Total	211,245
Municipal securities.
Securities HTM:
Securities HTM, Amortized cost	561,099	586,272
Securities held to maturity, fair value	527,934	534,586
Securities AFS:
Securities AFS, Amortized Cost	209,875	239,812
Available-for-sale Securities, Debt Securities, Total	170,590	193,178
Municipal securities. | Callable Securities [Member]
Securities HTM:
Securities held to maturity, callable, amortized cost	268,957
Securities held to maturity, callable, fair value	242,766
Securities AFS:
Securities available for sale, callable, amortized cost	206,954
Securities available for sale, callable, fair value	167,686
Asset-backed securities
Securities AFS:
Securities AFS, Amortized Cost	18,087	18,885
Available-for-sale Securities, Debt Securities, Total	17,967	18,728
Securities available for sale, callable, amortized cost	18,087
Securities available for sale, callable, fair value	17,967
Residential mortgage-backed and related securities
Securities AFS:
Securities AFS, Amortized Cost	69,415	73,438
Available-for-sale Securities, Debt Securities, Total	63,104	66,215
Securities available for sale, callable, amortized cost	69,415
Securities available for sale, callable, fair value	63,104
Other securities
Securities HTM:
Securities HTM, Amortized cost	1,050	1,050
Securities held to maturity, fair value	1,032	1,050
Securities AFS:
Securities AFS, Amortized Cost	48,562	48,631
Available-for-sale Securities, Debt Securities, Total	44,496	$ 45,858
Other securities | Callable Securities [Member]
Securities AFS:
Securities available for sale, callable, amortized cost	47,610
Securities available for sale, callable, fair value	$ 43,559