INVESTMENT SECURITIES - Schedule of Gross Unrealized Losses and Fair Value of Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024
Estimated Fair Value
Less Than 12 Months	$ 214,037	$ 507,188
12 Months or More	890,239	878,229
Total	1,104,276	1,385,417
Unrealized Losses
Less Than 12 Months	(802)	(3,696)
12 Months or More	(24,982)	(35,342)
Total	(25,784)	(39,038)
U.S. Treasuries
Estimated Fair Value
Less Than 12 Months	125,476	272,564
12 Months or More	329,568	353,787
Total	455,044	626,351
Unrealized Losses
Less Than 12 Months	(88)	(1,376)
12 Months or More	(1,333)	(3,689)
Total	(1,421)	(5,065)
U.S. government-sponsored agencies
Estimated Fair Value
Less Than 12 Months	0	0
12 Months or More	996	994
Total	996	994
Unrealized Losses
Less Than 12 Months	0	0
12 Months or More	(11)	(16)
Total	(11)	(16)
State, county and municipal securities
Estimated Fair Value
Less Than 12 Months	512	3,953
12 Months or More	15,959	15,940
Total	16,471	19,893
Unrealized Losses
Less Than 12 Months	(6)	(17)
12 Months or More	(970)	(1,053)
Total	(976)	(1,070)
Corporate debt securities
Estimated Fair Value
Less Than 12 Months	395	383
12 Months or More	8,547	8,400
Total	8,942	8,783
Unrealized Losses
Less Than 12 Months	(1)	(13)
12 Months or More	(434)	(581)
Total	(435)	(594)
SBA pool securities
Estimated Fair Value
Less Than 12 Months	36	52,850
12 Months or More	40,438	17,491
Total	40,474	70,341
Unrealized Losses
Less Than 12 Months	0	(322)
12 Months or More	(1,084)	(1,232)
Total	(1,084)	(1,554)
Mortgage-backed securities
Estimated Fair Value
Less Than 12 Months	87,618	177,438
12 Months or More	494,731	481,617
Total	582,349	659,055
Unrealized Losses
Less Than 12 Months	(707)	(1,968)
12 Months or More	(21,150)	(28,771)
Total	$ (21,857)	$ (30,739)