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INVESTMENT SECURITIES - Investment securities in a continuous unrealized loss position (Details) $ in Thousands | Mar. 31, 2025 USD ($) position | Dec. 31, 2024 USD ($)
--- | --- | ---
Available-for-Sale Securities, in Unrealized Loss Position, Fair Value |  |
Less than 12 months | $ 59,707 | $ 55,087
12 months or longer | 2,733,668 | 2,689,972
Total | 2,793,375 | 2,745,059
Available-for-Sale Securities, in Unrealized Loss Position, Gross Unrealized Losses |  |
Less than 12 months | 2,076 | 1,068
12 months or longer | 353,618 | 405,935
Total | 355,694 | 407,003
Fair Value |  |
Less than 12 Months | 116,129 | 149,742
12 Months or Longer | 1,080,504 | 1,030,830
Total | 1,196,633 | 1,180,572
Gross Unrealized Losses |  |
Less than 12 Months | 869 | 2,027
12 Months or Longer | 87,631 | 123,408
Total | 88,500 | 125,435
Unrealized losses in provision for credit losses | 0 |
Available-for-sale, allowance for credit losses | 0 |
Accrued interest receivable on available-for-sale debt securities | $ 8,600 |
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration] | Interest Receivable |
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 | 2,134,917 | 2,083,786
Total | 2,134,917 | 2,083,786
Available-for-Sale Securities, in Unrealized Loss Position, Gross Unrealized Losses |  |
Less than 12 months | 0 | 0
12 months or longer | 256,733 | 305,422
Total | 256,733 | 305,422
Fair Value |  |
Less than 12 Months | 0 | 0
12 Months or Longer | 1,058,570 | 1,015,549
Total | 1,058,570 | 1,015,549
Gross Unrealized Losses |  |
Less than 12 Months | 0 | 0
12 Months or Longer | 87,496 | 123,194
Total | 87,496 | 123,194
Obligations of state and political subdivisions |  |
Available-for-Sale Securities, in Unrealized Loss Position, Fair Value |  |
Less than 12 months | 52,985 | 47,144
12 months or longer | 295,396 | 301,202
Total | 348,381 | 348,346
Available-for-Sale Securities, in Unrealized Loss Position, Gross Unrealized Losses |  |
Less than 12 months | 1,954 | 847
12 months or longer | 44,306 | 41,150
Total | 46,260 | 41,997
Government agency mortgage-backed securities |  |
Available-for-Sale Securities, in Unrealized Loss Position, Fair Value |  |
Less than 12 months | 6,722 | 7,943
12 months or longer | 289,643 | 290,786
Total | 296,365 | 298,729
Available-for-Sale Securities, in Unrealized Loss Position, Gross Unrealized Losses |  |
Less than 12 months | 122 | 221
12 months or longer | 52,056 | 58,694
Total | 52,178 | 58,915
Fair Value |  |
Less than 12 Months | 116,129 | 149,742
12 Months or Longer | 21,934 | 15,281
Total | 138,063 | 165,023
Gross Unrealized Losses |  |
Less than 12 Months | 869 | 2,027
12 Months or Longer | 135 | 214
Total | $ 1,004 | 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 | 2 |
Available-for-Sale Securities, in Unrealized Loss Position, Fair Value |  |
Less than 12 months | $ 0 | 0
12 months or longer | 7,771 | 7,697
Total | 7,771 | 7,697
Available-for-Sale Securities, in Unrealized Loss Position, Gross Unrealized Losses |  |
Less than 12 months | 0 | 0
12 months or longer | 229 | 303
Total | 229 | 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 | 5,941 | 6,501
Total | 5,941 | 6,501
Available-for-Sale Securities, in Unrealized Loss Position, Gross Unrealized Losses |  |
Less than 12 months | 0 | 0
12 months or longer | 294 | 366
Total | $ 294 | $ 366

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