LOANS AND ALLOWANCE FOR CREDIT LOSSES - Summary of Amounts of Commitments (Details) - USD ($) $ in Thousands |
Sep. 30, 2026 |
Dec. 31, 2025 |
|---|---|---|
| Loan commitments to extend credit | ||
| Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items] | ||
| Amounts of commitments | $ 6,080,902 | $ 5,586,510 |
| Standby letters of credit | ||
| Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items] | ||
| Amounts of commitments | $ 109,924 | $ 73,997 |