SECURITIES - Amortized Cost and Fair Value of Investment Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 1,545,130	$ 1,988,916
Gross Unrealized Gains	2,303	4,773
Gross Unrealized Losses	(151,753)	(186,103)
Fair Value	1,395,680	1,807,586
U.S. government and agency securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	307,529	433,417
Gross Unrealized Gains	90	90
Gross Unrealized Losses	(10,201)	(19,227)
Fair Value	297,418	414,280
Municipal securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	229,615	580,076
Gross Unrealized Gains	1,615	4,319
Gross Unrealized Losses	(27,171)	(43,826)
Fair Value	204,059	540,569
Agency mortgage-backed pass-through securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	424,664	370,471
Gross Unrealized Gains	370	362
Gross Unrealized Losses	(37,161)	(42,032)
Fair Value	387,873	328,801
Agency collateralized mortgage obligations
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	462,498	461,760
Gross Unrealized Gains	172	0
Gross Unrealized Losses	(64,553)	(67,630)
Fair Value	398,117	394,130
Corporate bonds and other
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	120,824	143,192
Gross Unrealized Gains	56	2
Gross Unrealized Losses	(12,667)	(13,388)
Fair Value	$ 108,213	$ 129,806