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INVESTMENT SECURITIES - Investment securities in a continuous unrealized loss position (Details) $ in Thousands | Dec. 31, 2022 USD ($) position | Dec. 31, 2021 USD ($) position
--- | --- | ---
Number of positions |  |
Less than 12 months | position | 1,149 | 240
12 months or longer | position | 430 | 66
Total | position | 1,579 | 306
Fair Value |  |
Less than 12 months | $ 1,955,294 | $ 1,395,578
12 months or longer | 2,106,692 | 967,788
Total | 4,061,986 | 2,363,366
Gross Unrealized Losses |  |
Less than 12 months | 188,107 | 17,505
12 months or longer | 336,081 | 93,774
Total | 524,188 | 111,279
Available-for-sale, allowance for credit losses | $ 0 | $ 0
Number of positions |  |
Less than 12 Months | position | 23 |
12 Months or Longer | position | 0 |
Total | position | 23 |
Fair Value |  |
Less than 12 Months | $ 1,034,795 |
12 Months or Longer | 0 |
Total | 1,034,795 |
Gross Unrealized Losses |  |
Less than 12 Months | 44,900 |
12 Months or Longer | 0 |
Total | $ 44,900 |
U.S. Treasury and agency securities |  |
Number of positions |  |
Less than 12 months | position | 41 | 47
12 months or longer | position | 61 | 13
Total | position | 102 | 60
Fair Value |  |
Less than 12 months | $ 1,384,075 | $ 1,224,101
12 months or longer | 1,859,462 | 900,462
Total | 3,243,537 | 2,124,563
Gross Unrealized Losses |  |
Less than 12 months | 132,511 | 14,873
12 months or longer | 284,498 | 91,184
Total | $ 417,009 | $ 106,057
Number of positions |  |
Less than 12 Months | position | 23 |
12 Months or Longer | position | 0 |
Total | position | 23 |
Fair Value |  |
Less than 12 Months | $ 1,034,795 |
12 Months or Longer | 0 |
Total | 1,034,795 |
Gross Unrealized Losses |  |
Less than 12 Months | 44,900 |
12 Months or Longer | 0 |
Total | $ 44,900 |
Obligations of state and political subdivisions |  |
Number of positions |  |
Less than 12 months | position | 582 | 27
12 months or longer | position | 76 | 0
Total | position | 658 | 27
Fair Value |  |
Less than 12 months | $ 370,524 | $ 23,966
12 months or longer | 47,923 | 0
Total | 418,447 | 23,966
Gross Unrealized Losses |  |
Less than 12 months | 35,488 | 56
12 months or longer | 9,839 | 0
Total | $ 45,327 | $ 56
Government agency mortgage-backed securities |  |
Number of positions |  |
Less than 12 months | position | 497 | 147
12 months or longer | position | 274 | 52
Total | position | 771 | 199
Fair Value |  |
Less than 12 months | $ 190,727 | $ 139,442
12 months or longer | 189,919 | 67,273
Total | 380,646 | 206,715
Gross Unrealized Losses |  |
Less than 12 months | 19,508 | 2,475
12 months or longer | 40,606 | 2,590
Total | $ 60,114 | $ 5,065
Corporate debt securities |  |
Number of positions |  |
Less than 12 months | position | 0 | 1
12 months or longer | position | 2 | 0
Total | position | 2 | 1
Fair Value |  |
Less than 12 months | $ 0 | $ 4,923
12 months or longer | 7,114 | 0
Total | 7,114 | 4,923
Gross Unrealized Losses |  |
Less than 12 months | 0 | 77
12 months or longer | 886 | 0
Total | $ 886 | $ 77
Government agency collateralized mortgage obligations |  |
Number of positions |  |
Less than 12 months | position | 29 | 18
12 months or longer | position | 17 | 1
Total | position | 46 | 19
Fair Value |  |
Less than 12 months | $ 9,968 | $ 3,146
12 months or longer | 2,274 | 53
Total | 12,242 | 3,199
Gross Unrealized Losses |  |
Less than 12 months | 600 | 24
12 months or longer | 252 | 0
Total | $ 852 | $ 24

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