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FAIR VALUE - Unobservable Inputs Used to Measure Fair Value (Details) $ in Thousands | Sep. 30, 2025 USD ($) | Jun. 30, 2025 USD ($) | Dec. 31, 2024 USD ($)
--- | --- | --- | ---
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities AFS, Fair value | $ 3,490,478 |  | $ 3,065,251
Interest rate lock commitments, net |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Interest rate lock commitments, net | 277 | $ 0 | 0
Recurring |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities AFS, Fair value | 3,490,478 |  | 3,065,251
Recurring | Level 3 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities AFS, Fair value | 1,659 |  | $ 0
Recurring | Level 3 | Interest rate lock commitments, net |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Interest rate lock commitments, net | $ 277 |  |
Implied spread to benchmark interest rate curve | Minimum | Recurring | Level 3 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Implied spread to benchmark interest rate curve | 0.0225 |  |
Implied spread to benchmark interest rate curve | Maximum | Recurring | Level 3 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Implied spread to benchmark interest rate curve | 0.0225 |  |
Implied spread to benchmark interest rate curve | Weighted Average | Recurring | Level 3 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Implied spread to benchmark interest rate curve | 0.0225 |  |
Fall-out factor | Minimum | Recurring | Level 3 | Interest rate lock commitments, net |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Fall-out factor/Value of servicing | 0.0110 |  |
Fall-out factor | Maximum | Recurring | Level 3 | Interest rate lock commitments, net |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Fall-out factor/Value of servicing | 0.2454 |  |
Fall-out factor | Weighted Average | Recurring | Level 3 | Interest rate lock commitments, net |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Fall-out factor/Value of servicing | 0.1504 |  |
Value of servicing | Minimum | Recurring | Level 3 | Interest rate lock commitments, net |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Fall-out factor/Value of servicing | 0.0064 |  |
Value of servicing | Maximum | Recurring | Level 3 | Interest rate lock commitments, net |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Fall-out factor/Value of servicing | 0.0149 |  |
Value of servicing | Weighted Average | Recurring | Level 3 | Interest rate lock commitments, net |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Fall-out factor/Value of servicing | 0.0118 |  |

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