NONINTEREST INCOME - Investment Management and Fiduciary Income (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Investment management and fiduciary income
Revenue from External Customer [Line Items]
Noninterest income	$ 32,379	$ 31,192	$ 62,855	$ 61,373
Trust fees
Revenue from External Customer [Line Items]
Noninterest income	21,936	20,398	42,452	39,488
Wealth management and advisory fees
Revenue from External Customer [Line Items]
Noninterest income	$ 10,443	$ 10,794	$ 20,403	$ 21,885