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INVESTMENT SECURITIES - Amortized Cost and Estimated Fair Value of Investment Securities Available for Sale (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 1,559,005	$ 572,887
Allowance for Credit Losses	(75)	0	$ (112)	$ 0
Gross Unrealized Gains	264	19,929
Gross Unrealized Losses	(59,134)	(195)
Estimated Fair Value	1,500,060	592,621
U.S. Treasuries
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	775,784
Allowance for Credit Losses	0
Gross Unrealized Gains	131
Gross Unrealized Losses	(16,381)
Estimated Fair Value	759,534
U.S. government-sponsored agencies
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,036	7,084
Allowance for Credit Losses	0	0
Gross Unrealized Gains	0	88
Gross Unrealized Losses	(57)	0
Estimated Fair Value	979	7,172
State, county and municipal securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	35,358	45,470
Allowance for Credit Losses	0	0
Gross Unrealized Gains	17	2,342
Gross Unrealized Losses	(1,180)	0
Estimated Fair Value	34,195	47,812
Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	16,397	27,897
Allowance for Credit Losses	(75)	0
Gross Unrealized Gains	0	719
Gross Unrealized Losses	(396)	(120)
Estimated Fair Value	15,926	28,496
SBA pool securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	29,422	44,312
Allowance for Credit Losses	0	0
Gross Unrealized Gains	3	958
Gross Unrealized Losses	(2,027)	(69)
Estimated Fair Value	27,398	45,201
Mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	701,008	448,124
Allowance for Credit Losses	0	0
Gross Unrealized Gains	113	15,822
Gross Unrealized Losses	(39,093)	(6)
Estimated Fair Value	$ 662,028	$ 463,940