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DEBT SECURITIES - Schedule of Debt Securities in an Unrealized or Unrecognized Loss Position (Details) - USD ($) $ in Thousands | Sep. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Fair Value |  |
Less than 12 months | $ 182,678 | $ 185,148
12 months or more | 980,555 | 1,281,595
Total | 1,163,233 | 1,466,743
Unrealized Losses |  |
Less than 12 months | (2,650) | (895)
12 months or more | (159,575) | (229,430)
Total | (162,225) | (230,325)
Fair Value |  |
12 months or more | 659,471 | 675,053
Total | 659,471 | 675,053
Unrecognized Losses |  |
12 months or more | (125,350) | (151,577)
Total | (125,350) | (151,577)
Obligations of U.S. government corporations and agencies |  |
Fair Value |  |
Less than 12 months | 69,984 | 0
12 months or more | 0 | 1,328
Total | 69,984 | 1,328
Unrealized Losses |  |
Less than 12 months | (195) | 0
12 months or more | 0 | (8)
Total | (195) | (8)
Obligations of states and political subdivisions |  |
Fair Value |  |
Less than 12 months | 99,487 | 11,234
12 months or more | 95,200 | 119,723
Total | 194,687 | 130,957
Unrealized Losses |  |
Less than 12 months | (2,375) | (209)
12 months or more | (10,206) | (16,527)
Total | (12,581) | (16,736)
Asset-backed securities |  |
Fair Value |  |
Less than 12 months |  | 14,997
12 months or more |  | 0
Total |  | 14,997
Unrealized Losses |  |
Less than 12 months |  | (3)
12 months or more |  | 0
Total |  | (3)
Commercial mortgage-backed securities |  |
Fair Value |  |
Less than 12 months | 5,813 | 6,238
12 months or more | 72,141 | 85,936
Total | 77,954 | 92,174
Unrealized Losses |  |
Less than 12 months | (61) | (42)
12 months or more | (11,682) | (15,089)
Total | (11,743) | (15,131)
Fair Value |  |
12 months or more | 329,632 | 338,288
Total | 329,632 | 338,288
Unrecognized Losses |  |
12 months or more | (68,743) | (77,242)
Total | (68,743) | (77,242)
Residential mortgage-backed securities |  |
Fair Value |  |
Less than 12 months | 1,427 | 152,081
12 months or more | 782,258 | 930,642
Total | 783,685 | 1,082,723
Unrealized Losses |  |
Less than 12 months | (1) | (640)
12 months or more | (135,785) | (191,259)
Total | (135,786) | (191,899)
Fair Value |  |
12 months or more | 329,839 | 336,765
Total | 329,839 | 336,765
Unrecognized Losses |  |
12 months or more | (56,607) | (74,335)
Total | (56,607) | (74,335)
Corporate debt securities |  |
Fair Value |  |
Less than 12 months | 5,967 | 598
12 months or more | 30,956 | 143,966
Total | 36,923 | 144,564
Unrealized Losses |  |
Less than 12 months | (18) | (1)
12 months or more | (1,902) | (6,547)
Total | $ (1,920) | $ (6,548)

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