INVESTMENT SECURITIES - Continuous Unrealized Loss on Investment (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024
AFS
AFS, Less than 12 months, Gross unrealized losses	$ (542)	$ (890)
AFS, Less than 12 months, Fair value	30,843	36,374
AFS, Twelve months or more, Gross unrealized losses	(107,049)	(115,029)
AFS, Twelve months or more, Fair value	934,828	945,595
AFS, Total, Gross unrealized losses	(107,591)	(115,919)
AFS, Total, Fair value	965,671	981,969
Residential
AFS
AFS, Less than 12 months, Gross unrealized losses	(1)	(2)
AFS, Less than 12 months, Fair value	530	532
AFS, Twelve months or more, Gross unrealized losses	(5,486)	(7,652)
AFS, Twelve months or more, Fair value	155,525	158,044
AFS, Total, Gross unrealized losses	(5,487)	(7,654)
AFS, Total, Fair value	156,055	158,576
Commercial
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	(5,969)	(6,978)
AFS, Twelve months or more, Fair value	48,462	47,642
AFS, Total, Gross unrealized losses	(5,969)	(6,978)
AFS, Total, Fair value	48,462	47,642
Residential collateralized mortgage obligations
AFS
AFS, Less than 12 months, Gross unrealized losses	(9)	(78)
AFS, Less than 12 months, Fair value	5,394	7,481
AFS, Twelve months or more, Gross unrealized losses	(26,935)	(31,862)
AFS, Twelve months or more, Fair value	278,518	293,297
AFS, Total, Gross unrealized losses	(26,944)	(31,940)
AFS, Total, Fair value	283,912	300,778
Commercial collateralized mortgage obligations
AFS
AFS, Less than 12 months, Gross unrealized losses	(2)	0
AFS, Less than 12 months, Fair value	3,081	0
AFS, Twelve months or more, Gross unrealized losses	(4,049)	(4,794)
AFS, Twelve months or more, Fair value	50,074	51,834
AFS, Total, Gross unrealized losses	(4,051)	(4,794)
AFS, Total, Fair value	53,155	51,834
Municipal bonds
AFS
AFS, Less than 12 months, Gross unrealized losses	(530)	(810)
AFS, Less than 12 months, Fair value	21,838	28,361
AFS, Twelve months or more, Gross unrealized losses	(56,332)	(54,188)
AFS, Twelve months or more, Fair value	347,214	340,571
AFS, Total, Gross unrealized losses	(56,862)	(54,998)
AFS, Total, Fair value	369,052	368,932
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	(17)	(28)
HFM, 12 months or more, Fair value	2,266	2,273
HFM, Total, Gross unrealized losses	(17)	(28)
HTM, Total, Fair value	2,266	2,273
Corporate debt 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	(5,539)	(6,192)
AFS, Twelve months or more, Fair value	25,590	24,944
AFS, Total, Gross unrealized losses	(5,539)	(6,192)
AFS, Total, Fair value	25,590	24,944
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	(1,901)	(2,319)
AFS, Twelve months or more, Fair value	20,317	19,987
AFS, Total, Gross unrealized losses	(1,901)	(2,319)
AFS, Total, Fair value	20,317	19,987
Agency debentures
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	(838)	(1,044)
AFS, Twelve months or more, Fair value	9,128	9,276
AFS, Total, Gross unrealized losses	(838)	(1,044)
AFS, Total, Fair value	$ 9,128	$ 9,276

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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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Amount of accumulated unrealized loss on 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 12 months or longer, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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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 less than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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