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DEBT SECURITIES - Schedule of Additional Information on Debt Securities In Unrealized or Unrecognized Loss Position (Details) $ in Thousands | Sep. 30, 2025 USD ($) security | Dec. 31, 2024 USD ($) security
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Available for Sale |  |
Debt securities with gross unrealized or unrecognized losses, fair value | $ | $ 1,163,233 | $ 1,466,743
Gross unrealized or unrecognized losses on debt securities | $ | $ 162,225 | $ 230,325
Ratio of gross unrealized or unrecognized losses to debt securities with gross unrealized or unrecognized losses | 13.90% | 15.70%
Count of debt securities | security | 632 | 677
Count of debt securities in an unrealized or unrecognized loss position | security | 428 | 586
Held to Maturity |  |
Debt securities with gross unrealized or unrecognized losses, fair value | $ | $ 659,471 | $ 675,053
Gross unrealized or unrecognized losses on debt securities | $ | $ 125,350 | $ 151,577
Ratio of gross unrealized or unrecognized losses to debt securities with gross unrealized or unrecognized losses | 19.00% | 22.50%
Count of debt securities | security | 55 | 55
Count of debt securities in an unrealized or unrecognized loss position | security | 55 | 55
Total |  |
Debt securities with gross unrealized or unrecognized losses, fair value | $ | $ 1,822,704 | $ 2,141,796
Gross unrealized or unrecognized losses on debt securities | $ | $ 287,575 | $ 381,902
Ratio of gross unrealized or unrecognized losses to debt securities with gross unrealized or unrecognized losses | 15.80% | 17.80%
Count of debt securities | security | 687 | 732
Count of debt securities in an unrealized or unrecognized loss position | security | 483 | 641

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