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INVESTMENT SECURITIES - Investment securities in a continuous unrealized loss position (Details) $ in Thousands | Jun. 30, 2025 USD ($) position | Dec. 31, 2024 USD ($)
--- | --- | ---
Available-for-Sale Securities, in Unrealized Loss Position, Fair Value |  |
Less than 12 months | $ 52,551 | $ 55,087
12 months or longer | 2,739,857 | 2,689,972
Total | 2,792,408 | 2,745,059
Available-for-Sale Securities, in Unrealized Loss Position, Gross Unrealized Losses |  |
Less than 12 months | 2,480 | 1,068
12 months or longer | 334,920 | 405,935
Total | 337,400 | 407,003
Fair Value |  |
Less than 12 Months | 113,516 | 149,742
12 Months or Longer | 1,075,378 | 1,030,830
Total | 1,188,894 | 1,180,572
Gross Unrealized Losses |  |
Less than 12 Months | 781 | 2,027
12 Months or Longer | 95,386 | 123,408
Total | 96,167 | 125,435
Unrealized losses in provision for credit losses | 0 |
Available-for-sale, allowance for credit losses | 0 |
Debt Securities, Held-to-Maturity, Accrued Interest, after Allowance for Credit Loss | 10,600 |
U.S. Treasury and agency securities |  |
Available-for-Sale Securities, in Unrealized Loss Position, Fair Value |  |
Less than 12 months | 0 | 0
12 months or longer | 2,154,944 | 2,083,786
Total | 2,154,944 | 2,083,786
Available-for-Sale Securities, in Unrealized Loss Position, Gross Unrealized Losses |  |
Less than 12 months | 0 | 0
12 months or longer | 239,341 | 305,422
Total | 239,341 | 305,422
Fair Value |  |
Less than 12 Months | 0 | 0
12 Months or Longer | 1,058,180 | 1,015,549
Total | 1,058,180 | 1,015,549
Gross Unrealized Losses |  |
Less than 12 Months | 0 | 0
12 Months or Longer | 95,300 | 123,194
Total | 95,300 | 123,194
Obligations of state and political subdivisions |  |
Available-for-Sale Securities, in Unrealized Loss Position, Fair Value |  |
Less than 12 months | 45,983 | 47,144
12 months or longer | 292,583 | 301,202
Total | 338,566 | 348,346
Available-for-Sale Securities, in Unrealized Loss Position, Gross Unrealized Losses |  |
Less than 12 months | 2,364 | 847
12 months or longer | 43,717 | 41,150
Total | 46,081 | 41,997
Government agency mortgage-backed securities |  |
Available-for-Sale Securities, in Unrealized Loss Position, Fair Value |  |
Less than 12 months | 6,568 | 7,943
12 months or longer | 282,078 | 290,786
Total | 288,646 | 298,729
Available-for-Sale Securities, in Unrealized Loss Position, Gross Unrealized Losses |  |
Less than 12 months | 116 | 221
12 months or longer | 51,436 | 58,694
Total | 51,552 | 58,915
Fair Value |  |
Less than 12 Months | 113,516 | 149,742
12 Months or Longer | 17,198 | 15,281
Total | 130,714 | 165,023
Gross Unrealized Losses |  |
Less than 12 Months | 781 | 2,027
12 Months or Longer | 86 | 214
Total | $ 867 | 2,241
Corporate debt securities |  |
Available-for-Sale Securities in Unrealized Loss Positions, Number of Positions |  |
Debt securities, available-for-sale, unrealized loss Position, number of positions | position | 1 |
Available-for-Sale Securities, in Unrealized Loss Position, Fair Value |  |
Less than 12 months | $ 0 | 0
12 months or longer | 4,829 | 7,697
Total | 4,829 | 7,697
Available-for-Sale Securities, in Unrealized Loss Position, Gross Unrealized Losses |  |
Less than 12 months | 0 | 0
12 months or longer | 171 | 303
Total | 171 | 303
Government agency collateralized mortgage obligations |  |
Available-for-Sale Securities, in Unrealized Loss Position, Fair Value |  |
Less than 12 months | 0 | 0
12 months or longer | 5,423 | 6,501
Total | 5,423 | 6,501
Available-for-Sale Securities, in Unrealized Loss Position, Gross Unrealized Losses |  |
Less than 12 months | 0 | 0
12 months or longer | 255 | 366
Total | $ 255 | $ 366

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