INVESTMENT SECURITIES - Continuous Unrealized Loss on Investment (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
AFS
AFS, Less than 12 months, Gross unrealized losses	$ (364)	$ (579)
AFS, Less than 12 months, Fair value	38,123	135,407
AFS, Twelve months or more, Gross unrealized losses	(123,590)	(115,685)
AFS, Twelve months or more, Fair value	1,061,994	1,055,874
AFS, Total, Gross unrealized losses	(123,954)	(116,264)
AFS, Total, Fair value	1,100,117	1,191,281
Residential mortgage-backed securities
AFS
AFS, Less than 12 months, Gross unrealized losses	(1)	(3)
AFS, Less than 12 months, Fair value	426	1,145
AFS, Twelve months or more, Gross unrealized losses	(10,721)	(10,457)
AFS, Twelve months or more, Fair value	167,595	177,393
AFS, Total, Gross unrealized losses	(10,722)	(10,460)
AFS, Total, Fair value	168,021	178,538
Commercial mortgage-backed securities
AFS
AFS, Less than 12 months, Gross unrealized losses	0	0
AFS, Less than 12 months, Fair value	0	61
AFS, Twelve months or more, Gross unrealized losses	(7,511)	(7,479)
AFS, Twelve months or more, Fair value	47,421	47,695
AFS, Total, Gross unrealized losses	(7,511)	(7,479)
AFS, Total, Fair value	47,421	47,756
Residential collateralized mortgage obligations
AFS
AFS, Less than 12 months, Gross unrealized losses	0	(368)
AFS, Less than 12 months, Fair value	2,066	83,815
AFS, Twelve months or more, Gross unrealized losses	(35,193)	(33,171)
AFS, Twelve months or more, Fair value	339,438	348,914
AFS, Total, Gross unrealized losses	(35,193)	(33,539)
AFS, Total, Fair value	341,504	432,729
Commercial collateralized mortgage obligations
AFS
AFS, Less than 12 months, Gross unrealized losses	0	0
AFS, Less than 12 months, Fair value	0	0
AFS, Twelve months or more, Gross unrealized losses	(5,555)	(6,059)
AFS, Twelve months or more, Fair value	56,488	57,397
AFS, Total, Gross unrealized losses	(5,555)	(6,059)
AFS, Total, Fair value	56,488	57,397
Municipal bonds
AFS
AFS, Less than 12 months, Gross unrealized losses	(346)	(73)
AFS, Less than 12 months, Fair value	20,649	7,489
AFS, Twelve months or more, Gross unrealized losses	(54,308)	(47,780)
AFS, Twelve months or more, Fair value	358,287	364,775
AFS, Total, Gross unrealized losses	(54,654)	(47,853)
AFS, Total, Fair value	378,936	372,264
HTM
HFM, Less than 12 months, Gross unrealized losses	0	0
HFM, Less than 12 months, Fair value	0	0
HFM, 12 months or more, Gross unrealized losses	(45)	(40)
HFM, 12 months or more, Fair value	2,291	2,331
HFM, Total, Gross unrealized losses	(45)	(40)
HTM, Total, Fair value	2,291	2,331
Corporate debt securities
AFS
AFS, Less than 12 months, Gross unrealized losses	(8)	0
AFS, Less than 12 months, Fair value	9,991	0
AFS, Twelve months or more, Gross unrealized losses	(6,367)	(7,098)
AFS, Twelve months or more, Fair value	24,785	28,513
AFS, Total, Gross unrealized losses	(6,375)	(7,098)
AFS, Total, Fair value	34,776	28,513
U.S. Treasury securities
AFS
AFS, Less than 12 months, Gross unrealized losses	0	0
AFS, Less than 12 months, Fair value	0	0
AFS, Twelve months or more, Gross unrealized losses	(2,645)	(2,474)
AFS, Twelve months or more, Fair value	19,838	20,184
AFS, Total, Gross unrealized losses	(2,645)	(2,474)
AFS, Total, Fair value	19,838	20,184
Agency debentures
AFS
AFS, Less than 12 months, Gross unrealized losses	(9)	(135)
AFS, Less than 12 months, Fair value	4,991	42,897
AFS, Twelve months or more, Gross unrealized losses	(1,290)	(1,167)
AFS, Twelve months or more, Fair value	48,142	11,003
AFS, Total, Gross unrealized losses	(1,299)	(1,302)
AFS, Total, Fair value	$ 53,133	$ 53,900

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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