NOTE 2 - INVESTMENT SECURITIES - Amortized Cost and Fair Value of HTM and AFS Investment Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025	Mar. 31, 2025	Dec. 31, 2024
Securities HTM:
Pledged securities held to maturity, at amortized cost	$ 951,916	$ 948,676
Securities HTM, Amortized Cost	952,198	948,958
Securities HTM, Allowance for Credit (Losses)	(282)	(282)	$ (263)	$ (263)
Securities HTM, Gross Unrealized Gains	17,898	26,062
Securities HTM, Gross Unrealized (Losses)	(129,074)	(117,075)
Securities HTM, Fair Value	840,740	857,663
Securities AFS:
Securities AFS, Amortized Cost	340,215	326,752
Securities AFS, Gross Unrealized Gains	316	424
Securities AFS, Gross Unrealized (Losses)	(50,425)	(47,399)
Securities AFS, Fair Value	290,106	279,777
U.S. treasuries and govt. sponsored agency securities
Securities AFS:
Securities AFS, Amortized Cost	16,847	17,775
Securities AFS, Gross Unrealized Gains	3	4
Securities AFS, Gross Unrealized (Losses)	(1,791)	(1,755)
Securities AFS, Fair Value	15,059	16,024
Residential mortgage-backed and related securities
Securities AFS:
Securities AFS, Amortized Cost	90,911	72,951
Securities AFS, Gross Unrealized Gains	110	151
Securities AFS, Gross Unrealized (Losses)	(4,799)	(4,247)
Securities AFS, Fair Value	86,222	68,855
Municipal securities
Securities HTM:
Securities HTM, Amortized Cost	920,855	918,189
Securities HTM, Allowance for Credit (Losses)	(272)	(272)	(254)	(254)
Securities HTM, Gross Unrealized Gains	16,342	23,402
Securities HTM, Gross Unrealized (Losses)	(129,073)	(117,074)
Securities HTM, Fair Value	807,852	824,245
Securities AFS:
Securities AFS, Amortized Cost	203,399	203,613
Securities AFS, Gross Unrealized Gains		27
Securities AFS, Gross Unrealized (Losses)	(43,152)	(40,555)
Securities AFS, Fair Value	160,247	163,085
Asset-backed securities
Securities AFS:
Securities AFS, Amortized Cost	3,985	4,345
Securities AFS, Gross Unrealized Gains	91	94
Securities AFS, Fair Value	4,076	4,439
Corporate securities
Securities HTM:
Securities HTM, Amortized Cost	30,293	29,719
Securities HTM, Allowance for Credit (Losses)	(9)	(9)	(8)	(8)
Securities HTM, Gross Unrealized Gains	1,556	2,660
Securities HTM, Fair Value	31,840	32,370
Securities AFS:
Securities AFS, Amortized Cost	25,073	28,068
Securities AFS, Gross Unrealized Gains	112	148
Securities AFS, Gross Unrealized (Losses)	(683)	(842)
Securities AFS, Fair Value	24,502	27,374
Other securities
Securities HTM:
Securities HTM, Amortized Cost	1,050	1,050
Securities HTM, Allowance for Credit (Losses)	(1)	(1)	$ (1)	$ (1)
Securities HTM, Gross Unrealized (Losses)	(1)	(1)
Securities HTM, Fair Value	$ 1,048	$ 1,048

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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