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FAIR VALUE MEASUREMENTS - Unobservable Inputs Used to Measure Fair Value (Details) $ in Thousands	Mar. 31, 2026 USD ($)	Dec. 31, 2025 USD ($)	Mar. 31, 2025 USD ($)	Dec. 31, 2024 USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities AFS, Fair value	$ 3,933,705	$ 3,993,385
Interest rate lock commitments, net
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest rate lock commitments, net	120	75	$ 0	$ 0
Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities AFS, Fair value	3,933,705	3,993,385
Recurring \| Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities AFS, Fair value	1,594	1,630
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	$ 120	$ 75
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	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	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	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	0.0060
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	0.2060	0.2065
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	0.1194	0.1011
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	0.0093	0.0104
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	0.0156	0.0143
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	0.0125	0.0115