LOANS, ALLOWANCE FOR CREDIT LOSSES AND IMPAIRED LOANS - Schedule of Past Due (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Financing Receivable Recorded Investment Past Due [Line Items]
Total allowance for credit losses on loans	$ 1,460,792	$ 1,411,784
Current
Financing Receivable Recorded Investment Past Due [Line Items]
Total allowance for credit losses on loans	1,445,216	1,393,274
Current | Entity Loan Modification Program
Financing Receivable Recorded Investment Past Due [Line Items]
Total allowance for credit losses on loans	6,949
30-59 Days Past Due
Financing Receivable Recorded Investment Past Due [Line Items]
Total allowance for credit losses on loans	1,345	10,816
30-59 Days Past Due | Entity Loan Modification Program
Financing Receivable Recorded Investment Past Due [Line Items]
Total allowance for credit losses on loans	0
60-89 Days Past Due
Financing Receivable Recorded Investment Past Due [Line Items]
Total allowance for credit losses on loans	658	595
60-89 Days Past Due | Entity Loan Modification Program
Financing Receivable Recorded Investment Past Due [Line Items]
Total allowance for credit losses on loans	69
Greater Than 89 Days Past Due
Financing Receivable Recorded Investment Past Due [Line Items]
Total allowance for credit losses on loans	389	$ 246
Greater Than 89 Days Past Due | Entity Loan Modification Program
Financing Receivable Recorded Investment Past Due [Line Items]
Total allowance for credit losses on loans	0
Commercial real estate | Current | Entity Loan Modification Program
Financing Receivable Recorded Investment Past Due [Line Items]
Total allowance for credit losses on loans	4,694
Commercial real estate | 30-59 Days Past Due | Entity Loan Modification Program
Financing Receivable Recorded Investment Past Due [Line Items]
Total allowance for credit losses on loans	0
Commercial real estate | 60-89 Days Past Due | Entity Loan Modification Program
Financing Receivable Recorded Investment Past Due [Line Items]
Total allowance for credit losses on loans	0
Commercial real estate | Greater Than 89 Days Past Due | Entity Loan Modification Program
Financing Receivable Recorded Investment Past Due [Line Items]
Total allowance for credit losses on loans	0
Commercial and industrial | Current | Entity Loan Modification Program
Financing Receivable Recorded Investment Past Due [Line Items]
Total allowance for credit losses on loans	2,200
Commercial and industrial | 30-59 Days Past Due | Entity Loan Modification Program
Financing Receivable Recorded Investment Past Due [Line Items]
Total allowance for credit losses on loans	0
Commercial and industrial | 60-89 Days Past Due | Entity Loan Modification Program
Financing Receivable Recorded Investment Past Due [Line Items]
Total allowance for credit losses on loans	0
Commercial and industrial | Greater Than 89 Days Past Due | Entity Loan Modification Program
Financing Receivable Recorded Investment Past Due [Line Items]
Total allowance for credit losses on loans	0
Residential mortgage | Current | Entity Loan Modification Program
Financing Receivable Recorded Investment Past Due [Line Items]
Total allowance for credit losses on loans	35
Residential mortgage | 30-59 Days Past Due | Entity Loan Modification Program
Financing Receivable Recorded Investment Past Due [Line Items]
Total allowance for credit losses on loans	0
Residential mortgage | 60-89 Days Past Due | Entity Loan Modification Program
Financing Receivable Recorded Investment Past Due [Line Items]
Total allowance for credit losses on loans	69
Residential mortgage | Greater Than 89 Days Past Due | Entity Loan Modification Program
Financing Receivable Recorded Investment Past Due [Line Items]
Total allowance for credit losses on loans	0
Other consumer | Current | Entity Loan Modification Program
Financing Receivable Recorded Investment Past Due [Line Items]
Total allowance for credit losses on loans	20
Other consumer | 30-59 Days Past Due | Entity Loan Modification Program
Financing Receivable Recorded Investment Past Due [Line Items]
Total allowance for credit losses on loans	0
Other consumer | 60-89 Days Past Due | Entity Loan Modification Program
Financing Receivable Recorded Investment Past Due [Line Items]
Total allowance for credit losses on loans	0
Other consumer | Greater Than 89 Days Past Due | Entity Loan Modification Program
Financing Receivable Recorded Investment Past Due [Line Items]
Total allowance for credit losses on loans	$ 0