GOODWILL AND IDENTIFIABLE INTANGIBLE ASSETS (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2023	Dec. 31, 2022
Identifiable Intangible Assets
Gross carrying amount	$ 201,311	$ 197,186
Accumulated Amortization	(143,562)	(136,190)
Total	57,749	60,996
Estimated aggregate amortization expense for each of five succeeding fiscal years
Jul - Dec 2023	6,988
2024	12,435
2025	10,603
2026	9,350
2027	3,823
Thereafter	14,550
Total	57,749	60,996
Components of goodwill
Goodwill, beginning of period	841,841
Goodwill, activity	2,119
Goodwill, end of period	843,960
Core Deposit Intangibles
Identifiable Intangible Assets
Gross carrying amount	77,373	77,373
Accumulated Amortization	(67,348)	(65,069)
Total	10,025	12,304
Estimated aggregate amortization expense for each of five succeeding fiscal years
Total	10,025	12,304
Other Intangibles
Identifiable Intangible Assets
Gross carrying amount	123,938	119,813
Accumulated Amortization	(76,214)	(71,121)
Total	47,724	48,692
Estimated aggregate amortization expense for each of five succeeding fiscal years
Total	$ 47,724	$ 48,692