NOTE 2 - INVESTMENT SECURITIES - Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Securities held to maturity:
Securities held to maturity, due in one year or less, amortized cost	$ 3,016
Securities held to maturity, due in one year or less, fair value	3,023
Securities held to maturity, due after one year through five years, amortized cost	34,967
Securities held to maturity, due after one year through five years, fair value	35,545
Securities held to maturity, due after five years, amortized cost	393,300
Securities held to maturity, due after five years, fair value	411,833
Securities held to maturity, amortized cost	431,283
Securities held to maturity, fair value	450,401	$ 426,545
Securities available for sale:
Securities available for sale, due in one year or less, amortized cost	1,370
Securities available for sale, Due in one year or less, fair value	1,387
Securities available for sale, due after one year through five years, amortized cost	15,804
Securities available for sale, Due after one year through five years, fair value	16,131
Securities available for sale, due after five years, amortized cost	82,056
Securities available for sale, Due after five years, fair value	84,418
Securities available for sale, single maturity, amortized cost	99,230
Securities available for sale, single maturity, fair value	101,936
Securities available for sale, amortized cost	247,074	206,962
Securities available for sale, fair value	253,288	210,695
Callable Securities [Member]
Securities available for sale:
Securities available for sale, callable, amortized cost	65,594
Securities available for sale, callable, fair value	67,285
Municipal securities
Securities held to maturity:
Securities held to maturity, fair value	449,351	425,495
Securities available for sale:
Securities available for sale, amortized cost	61,432	46,659
Securities available for sale, fair value	63,431	48,257
Municipal securities | Callable Securities [Member]
Securities held to maturity:
Securities held to maturity, callable, amortized cost	199,843
Securities held to maturity, callable, fair value	201,706
Securities available for sale:
Securities available for sale, callable, amortized cost	47,044
Securities available for sale, callable, fair value	48,483
Asset-backed securities
Securities held to maturity:
Securities held to maturity, callable, amortized cost	31,076
Securities held to maturity, callable, fair value	28,499
Securities available for sale:
Securities available for sale, amortized cost	31,076	16,958
Securities available for sale, fair value	28,499	16,887
Residential mortgage-backed and related securities
Securities held to maturity:
Securities held to maturity, callable, amortized cost	116,768
Securities held to maturity, callable, fair value	122,853
Securities available for sale:
Securities available for sale, amortized cost	116,768	118,724
Securities available for sale, fair value	122,853	120,587
Other Securities
Securities held to maturity:
Securities held to maturity, fair value	1,050	1,050
Securities available for sale:
Securities available for sale, amortized cost	18,800	4,749
Securities available for sale, fair value	19,048	$ 4,886
Other Securities | Callable Securities [Member]
Securities available for sale:
Securities available for sale, callable, amortized cost	18,550
Securities available for sale, callable, fair value	$ 18,802