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DEBT SECURITIES - Schedule of Debt Securities in an Unrealized or Unrecognized Loss Position (Details) - USD ($) $ in Thousands | Sep. 30, 2024 | Dec. 31, 2023
--- | --- | ---
Fair Value |  |
Less than 12 months | $ 4,179 | $ 13,033
12 months or more | 1,369,246 | 2,049,784
Total | 1,373,425 | 2,062,817
Unrealized Losses |  |
Less than 12 months | (108) | (65)
12 months or more | (192,207) | (247,180)
Total | (192,315) | (247,245)
Fair Value |  |
12 months or more | 712,369 | 730,397
Total | 712,369 | 730,397
Unrecognized Losses |  |
12 months or more | (126,514) | (142,231)
Total | (126,514) | (142,231)
U.S. Treasury securities |  |
Fair Value |  |
Less than 12 months | 0 | 0
12 months or more | 250 | 15,946
Total | 250 | 15,946
Unrealized Losses |  |
Less than 12 months | 0 | 0
12 months or more | 0 | (85)
Total | 0 | (85)
Obligations of U.S. government corporations and agencies |  |
Fair Value |  |
Less than 12 months | 0 | 0
12 months or more | 1,425 | 5,709
Total | 1,425 | 5,709
Unrealized Losses |  |
Less than 12 months | 0 | 0
12 months or more | (7) | (58)
Total | (7) | (58)
Obligations of states and political subdivisions |  |
Fair Value |  |
Less than 12 months | 2,518 | 11,442
12 months or more | 134,373 | 146,797
Total | 136,891 | 158,239
Unrealized Losses |  |
Less than 12 months | (97) | (54)
12 months or more | (13,047) | (17,972)
Total | (13,144) | (18,026)
Asset-backed securities |  |
Fair Value |  |
Less than 12 months |  | 0
12 months or more |  | 468,223
Total |  | 468,223
Unrealized Losses |  |
Less than 12 months |  | 0
12 months or more |  | (1,823)
Total |  | (1,823)
Commercial mortgage-backed securities |  |
Fair Value |  |
Less than 12 months | 0 | 0
12 months or more | 89,272 | 103,509
Total | 89,272 | 103,509
Unrealized Losses |  |
Less than 12 months | 0 | 0
12 months or more | (12,492) | (15,535)
Total | (12,492) | (15,535)
Fair Value |  |
12 months or more | 354,905 | 357,526
Total | 354,905 | 357,526
Unrecognized Losses |  |
12 months or more | (64,780) | (71,000)
Total | (64,780) | (71,000)
Residential mortgage-backed securities |  |
Fair Value |  |
Less than 12 months | 877 | 141
12 months or more | 993,631 | 1,110,906
Total | 994,508 | 1,111,047
Unrealized Losses |  |
Less than 12 months | (2) | (1)
12 months or more | (159,223) | (195,546)
Total | (159,225) | (195,547)
Fair Value |  |
12 months or more | 357,464 | 372,871
Total | 357,464 | 372,871
Unrecognized Losses |  |
12 months or more | (61,734) | (71,231)
Total | (61,734) | (71,231)
Corporate debt securities |  |
Fair Value |  |
Less than 12 months | 784 | 1,450
12 months or more | 150,295 | 198,694
Total | 151,079 | 200,144
Unrealized Losses |  |
Less than 12 months | (9) | (10)
12 months or more | (7,438) | (16,161)
Total | $ (7,447) | $ (16,171)

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