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INVESTMENT SECURITIES - Investment Securities in a Continuous Unrealized Loss Position (Details) $ in Thousands | Jun. 30, 2023 USD ($) position | Dec. 31, 2022 USD ($) position
--- | --- | ---
Available-for-Sale Securities in Unrealized Loss Positions, Number of Positions |  |
Less than 12 months | position | 506 | 1,149
12 months or longer | position | 1,011 | 430
Total | position | 1,517 | 1,579
Available-for-Sale Securities, in Unrealized Loss Position, Fair Value |  |
Less than 12 months | $ 197,894 | $ 1,955,294
12 months or longer | 2,766,493 | 2,106,692
Total | 2,964,387 | 4,061,986
Available-for-Sale Securities, in Unrealized Loss Position, Gross Unrealized Losses |  |
Less than 12 months | 5,818 | 188,107
12 months or longer | 430,644 | 336,081
Total | $ 436,462 | $ 524,188
Number of positions |  |
Less than 12 Months | position | 29 | 23
12 Months or Longer | position | 0 | 0
Total | position | 29 | 23
Fair Value |  |
Less than 12 Months | $ 1,063,444 | $ 1,034,795
12 Months or Longer | 0 | 0
Total | 1,063,444 | 1,034,795
Gross Unrealized Losses |  |
Less than 12 Months | 40,576 | 44,900
12 Months or Longer | 0 | 0
Total | 40,576 | $ 44,900
Available-for-sale, allowance for credit losses | 0 |
Accrued interest receivable on available-for-sale debt securities | $ 12,700 |
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration] | Interest Receivable |
Accrued interest and fees receivable | $ 4,700 |
U.S. Treasury and agency securities |  |
Available-for-Sale Securities in Unrealized Loss Positions, Number of Positions |  |
Less than 12 months | position | 0 | 41
12 months or longer | position | 71 | 61
Total | position | 71 | 102
Available-for-Sale Securities, in Unrealized Loss Position, Fair Value |  |
Less than 12 months | $ 0 | $ 1,384,075
12 months or longer | 2,189,845 | 1,859,462
Total | 2,189,845 | 3,243,537
Available-for-Sale Securities, in Unrealized Loss Position, Gross Unrealized Losses |  |
Less than 12 months | 0 | 132,511
12 months or longer | 339,169 | 284,498
Total | $ 339,169 | $ 417,009
Number of positions |  |
Less than 12 Months | position | 23 | 23
12 Months or Longer | position | 0 | 0
Total | position | 23 | 23
Fair Value |  |
Less than 12 Months | $ 1,053,813 | $ 1,034,795
12 Months or Longer | 0 | 0
Total | 1,053,813 | 1,034,795
Gross Unrealized Losses |  |
Less than 12 Months | 40,454 | 44,900
12 Months or Longer | 0 | 0
Total | $ 40,454 | $ 44,900
Obligations of state and political subdivisions |  |
Available-for-Sale Securities in Unrealized Loss Positions, Number of Positions |  |
Less than 12 months | position | 296 | 582
12 months or longer | position | 326 | 76
Total | position | 622 | 658
Available-for-Sale Securities, in Unrealized Loss Position, Fair Value |  |
Less than 12 months | $ 159,626 | $ 370,524
12 months or longer | 234,244 | 47,923
Total | 393,870 | 418,447
Available-for-Sale Securities, in Unrealized Loss Position, Gross Unrealized Losses |  |
Less than 12 months | 4,042 | 35,488
12 months or longer | 34,494 | 9,839
Total | $ 38,536 | $ 45,327
Government agency mortgage-backed securities |  |
Available-for-Sale Securities in Unrealized Loss Positions, Number of Positions |  |
Less than 12 months | position | 206 | 497
12 months or longer | position | 575 | 274
Total | position | 781 | 771
Available-for-Sale Securities, in Unrealized Loss Position, Fair Value |  |
Less than 12 months | $ 37,877 | $ 190,727
12 months or longer | 325,263 | 189,919
Total | 363,140 | 380,646
Available-for-Sale Securities, in Unrealized Loss Position, Gross Unrealized Losses |  |
Less than 12 months | 1,762 | 19,508
12 months or longer | 55,282 | 40,606
Total | $ 57,044 | $ 60,114
Number of positions |  |
Less than 12 Months | position | 6 |
12 Months or Longer | position | 0 |
Total | position | 6 |
Fair Value |  |
Less than 12 Months | $ 9,631 |
12 Months or Longer | 0 |
Total | 9,631 |
Gross Unrealized Losses |  |
Less than 12 Months | 122 |
12 Months or Longer | 0 |
Total | $ 122 |
Corporate debt securities |  |
Available-for-Sale Securities in Unrealized Loss Positions, Number of Positions |  |
Less than 12 months | position | 0 | 0
12 months or longer | position | 2 | 2
Total | position | 2 | 2
Available-for-Sale Securities, in Unrealized Loss Position, Fair Value |  |
Less than 12 months | $ 0 | $ 0
12 months or longer | 7,097 | 7,114
Total | 7,097 | 7,114
Available-for-Sale Securities, in Unrealized Loss Position, Gross Unrealized Losses |  |
Less than 12 months | 0 | 0
12 months or longer | 903 | 886
Total | $ 903 | $ 886
Government agency collateralized mortgage obligations |  |
Available-for-Sale Securities in Unrealized Loss Positions, Number of Positions |  |
Less than 12 months | position | 4 | 29
12 months or longer | position | 37 | 17
Total | position | 41 | 46
Available-for-Sale Securities, in Unrealized Loss Position, Fair Value |  |
Less than 12 months | $ 391 | $ 9,968
12 months or longer | 10,044 | 2,274
Total | 10,435 | 12,242
Available-for-Sale Securities, in Unrealized Loss Position, Gross Unrealized Losses |  |
Less than 12 months | 14 | 600
12 months or longer | 796 | 252
Total | $ 810 | $ 852

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