ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) - Reclassifications (Loss) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Reclassification Adjustments out of Accumulated Other Comprehensive Income [Line Items]
Net realized gains (losses) on sales of available for sale securities	$ (6,930)	$ 1,194	$ 5,674
Income tax expense	(35,446)	(33,585)	(35,259)
Subordinated debentures and other borrowings	10,316	8,009	6,642
Salaries and employee benefits	228,745	206,893	166,995
Net income	223,786	222,089	205,531
Amount Reclassified from Accumulated Other Comprehensive Income (Loss)
Reclassification Adjustments out of Accumulated Other Comprehensive Income [Line Items]
Net income	(5,552)	466	3,591
Amount Reclassified from Accumulated Other Comprehensive Income (Loss) | Unrealized gains (losses) on available for sale securities
Reclassification Adjustments out of Accumulated Other Comprehensive Income [Line Items]
Net realized gains (losses) on sales of available for sale securities	(6,930)	1,194	5,674
Income tax expense	1,455	(251)	(1,192)
Net income	(5,475)	943	4,482
Amount Reclassified from Accumulated Other Comprehensive Income (Loss) | Unrealized gains (losses) on cash flow hedges
Reclassification Adjustments out of Accumulated Other Comprehensive Income [Line Items]
Income tax expense	3	109	219
Net income	(12)	(412)	(825)
Amount Reclassified from Accumulated Other Comprehensive Income (Loss) | Unrealized gains (losses) on cash flow hedges | Interest rate contracts
Reclassification Adjustments out of Accumulated Other Comprehensive Income [Line Items]
Subordinated debentures and other borrowings	(15)	(521)	(1,044)
Amount Reclassified from Accumulated Other Comprehensive Income (Loss) | Unrealized gains (losses) on defined benefit plans
Reclassification Adjustments out of Accumulated Other Comprehensive Income [Line Items]
Income tax expense	17	17	18
Salaries and employee benefits	(82)	(82)	(84)
Net income	$ (65)	$ (65)	$ (66)