DERIVATIVE FINANCIAL INSTRUMENTS AND HEDGING ACTIVITIES - Effect of cash flow hedging and fair value (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025
Loans
DERIVATIVE FINANCIAL INSTRUMENTS AND HEDGING ACTIVITIES
Income and expense line items presented in the consolidated statements of income	$ 48,658	$ 41,804
Securities and other
DERIVATIVE FINANCIAL INSTRUMENTS AND HEDGING ACTIVITIES
Income and expense line items presented in the consolidated statements of income	6,204	5,734
Deposits
DERIVATIVE FINANCIAL INSTRUMENTS AND HEDGING ACTIVITIES
Income and expense line items presented in the consolidated statements of income	14,889	15,512
Borrowings
DERIVATIVE FINANCIAL INSTRUMENTS AND HEDGING ACTIVITIES
Income and expense line items presented in the consolidated statements of income	3,489	3,019
Non-interest Income
DERIVATIVE FINANCIAL INSTRUMENTS AND HEDGING ACTIVITIES
Income and expense line items presented in the consolidated statements of income	10,414	8,918
Interest rate swap on wholesale funding \| Cash flow hedges \| Borrowings
DERIVATIVE FINANCIAL INSTRUMENTS AND HEDGING ACTIVITIES
Gain (loss) on cash flow hedges		252
Interest rate swap on variable rate loans \| Cash flow hedges \| Loans
DERIVATIVE FINANCIAL INSTRUMENTS AND HEDGING ACTIVITIES
Gain (loss) on cash flow hedges	(339)	(455)
Interest rate swap on securities \| Fair Value Hedging \| Securities and other
DERIVATIVE FINANCIAL INSTRUMENTS AND HEDGING ACTIVITIES
Gain (loss) on fair value hedges	$ 210	$ 275

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