DEBT SECURITIES - Schedule of Debt Securities in an Unrealized Loss Position (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Fair Value
Less than 12 months	$ 172,731	$ 185,148
12 months or more	958,493	1,281,595
Total	1,131,224	1,466,743
Unrealized Losses
Less than 12 months	(1,252)	(895)
12 months or more	(150,930)	(229,430)
Total	(152,182)	(230,325)
Fair Value
12 months or more	625,957	675,053
Total	625,957	675,053
Unrealized Losses
12 months or more	(120,428)	(151,577)
Total	(120,428)	(151,577)
Obligations of U.S. government corporations and agencies
Fair Value
Less than 12 months	39,156	0
12 months or more	0	1,328
Total	39,156	1,328
Unrealized Losses
Less than 12 months	(80)	0
12 months or more	0	(8)
Total	(80)	(8)
Obligations of states and political subdivisions
Fair Value
Less than 12 months	28,592	11,234
12 months or more	92,205	119,723
Total	120,797	130,957
Unrealized Losses
Less than 12 months	(361)	(209)
12 months or more	(9,537)	(16,527)
Total	(9,898)	(16,736)
Asset-backed securities
Fair Value
Less than 12 months	10,005	14,997
12 months or more	0	0
Total	10,005	14,997
Unrealized Losses
Less than 12 months	(35)	(3)
12 months or more	0	0
Total	(35)	(3)
Commercial mortgage-backed securities
Fair Value
Less than 12 months	4,986	6,238
12 months or more	71,830	85,936
Total	76,816	92,174
Unrealized Losses
Less than 12 months	(48)	(42)
12 months or more	(11,143)	(15,089)
Total	(11,191)	(15,131)
Fair Value
12 months or more	302,615	338,288
Total	302,615	338,288
Unrealized Losses
12 months or more	(65,210)	(77,242)
Total	(65,210)	(77,242)
Residential mortgage-backed securities
Fair Value
Less than 12 months	84,023	152,081
12 months or more	765,361	930,642
Total	849,384	1,082,723
Unrealized Losses
Less than 12 months	(708)	(640)
12 months or more	(128,559)	(191,259)
Total	(129,267)	(191,899)
Fair Value
12 months or more	323,342	336,765
Total	323,342	336,765
Unrealized Losses
12 months or more	(55,218)	(74,335)
Total	(55,218)	(74,335)
Corporate debt securities
Fair Value
Less than 12 months	5,969	598
12 months or more	29,097	143,966
Total	35,066	144,564
Unrealized Losses
Less than 12 months	(20)	(1)
12 months or more	(1,691)	(6,547)
Total	$ (1,711)	$ (6,548)

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