SECURITIES - Schedule of Securities Available for Sale (AFS) and Securities (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Securities available for sale
Amortized Cost	$ 1,211,212	$ 1,661,196
Gross Unrealized Gains	598	571
Gross Unrealized Losses	(189,525)	(238,567)
Fair Value	1,022,285	1,423,200
Allowance	0	0
Securities held to maturity
Amortized Cost	543,351	583,453
Gross Unrealized Gains	704	699
Gross Unrealized Losses	(67,827)	(76,688)
Fair Value	476,228	507,464
Securities held to maturity, Allowance	68	91	$ 105	$ 104
Marketable equity securities, Amortized Cost	15,035	15,035
Marketable equity securities, Gross Unrealized Gains	0	0
Marketable equity securities, Gross Unrealized Losses	(2,006)	(2,179)
Marketable equity securities, Fair Value	13,029	12,856
Amortized Cost	1,769,598	2,259,684
Gross Unrealized Gains	1,302	1,270
Gross Unrealized Losses	(259,358)	(317,434)
Fair Value	1,511,542	1,943,520
Allowance	68	91
U.S Treasuries
Securities available for sale
Amortized Cost	7,980	11,972
Gross Unrealized Gains	1	1
Gross Unrealized Losses	0	0
Fair Value	7,981	11,973
Allowance	0	0
Municipal bonds and obligations
Securities available for sale
Amortized Cost	64,788	65,943
Gross Unrealized Gains	494	422
Gross Unrealized Losses	(1,429)	(3,030)
Fair Value	63,853	63,335
Allowance	0	0
Securities held to maturity
Amortized Cost	251,046	266,793
Gross Unrealized Gains	698	691
Gross Unrealized Losses	(16,987)	(23,704)
Fair Value	234,757	243,780
Securities held to maturity, Allowance	48	66	70	64
Agency collateralized mortgage obligations
Securities available for sale
Amortized Cost	426,986	631,732
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(79,112)	(99,787)
Fair Value	347,874	531,945
Allowance	0	0
Securities held to maturity
Amortized Cost	112,929	128,136
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(18,360)	(20,420)
Fair Value	94,569	107,716
Securities held to maturity, Allowance	0	0
Agency mortgage-backed securities
Securities available for sale
Amortized Cost	492,633	643,308
Gross Unrealized Gains	2	1
Gross Unrealized Losses	(75,155)	(96,996)
Fair Value	417,480	546,313
Allowance	0	0
Securities held to maturity
Amortized Cost	47,379	50,958
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(8,052)	(9,240)
Fair Value	39,327	41,718
Securities held to maturity, Allowance	0	0
Agency commercial mortgage-backed securities
Securities available for sale
Amortized Cost	174,879	264,218
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(29,553)	(35,750)
Fair Value	145,326	228,468
Allowance	0	0
Securities held to maturity
Amortized Cost	130,169	135,206
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(24,368)	(23,203)
Fair Value	105,801	112,003
Securities held to maturity, Allowance	0	0
Corporate bonds
Securities available for sale
Amortized Cost	43,291	43,368
Gross Unrealized Gains	34	80
Gross Unrealized Losses	(4,210)	(2,938)
Fair Value	39,115	40,510
Allowance	0	0
Tax advantaged economic development bonds
Securities held to maturity
Amortized Cost	1,540	2,069
Gross Unrealized Gains	6	8
Gross Unrealized Losses	(60)	(121)
Fair Value	1,486	1,956
Securities held to maturity, Allowance	20	25	$ 35	$ 40
Other bonds and obligations
Securities available for sale
Amortized Cost	655	655
Gross Unrealized Gains	67	67
Gross Unrealized Losses	(66)	(66)
Fair Value	656	656
Allowance	0	0
Securities held to maturity
Amortized Cost	288	291
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	288	291
Securities held to maturity, Allowance	$ 0	$ 0