LOANS (Narrative) (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023	Dec. 31, 2022
Loans and Leases [Line Items]
Accrued interest receivable	$ 64,400,000		$ 64,400,000			$ 65,400,000
Unfunded commitments	0		0
Total Loans	11,608,309,000		11,608,309,000			12,068,645,000
Allowance for credit losses	126,861,000	$ 111,198,000	126,861,000	$ 111,198,000	$ 123,934,000	$ 122,566,000	$ 112,707,000	$ 109,483,000
Loans secured by residential real estate property in process of foreclosure	$ 1,100,000		$ 1,100,000
Loans delinquent 30 to 89 days, percentage	0.25%		0.25%			0.09%
Interest income on nonaccrual loans	$ 0	$ 0	$ 0	$ 0
Nonaccrual loans with no related allowance	28,100,000		28,100,000			$ 52,500,000
Paycheck Protection Program ("PPP")
Loans and Leases [Line Items]
Allowance for credit losses	0		0
Paycheck Protection Program ("PPP") | Nonpass
Loans and Leases [Line Items]
Total Loans	$ 223,000		$ 223,000			$ 136,000,000