FAIR VALUE OF FINANCIAL INSTRUMENTS - Individually evaluated loans (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Assets and Liabilities Measured at Fair Value on a Nonrecurring Basis [Abstract]
Individually evaluated loans outstanding balance, net of a valuation allowance	$ 10,688,515		$ 10,701,685
Allowance for credit losses	76,068		71,743
Provision (recovery) for credit losses	5,210	$ (3,648)
Nonrecurring
Assets and Liabilities Measured at Fair Value on a Nonrecurring Basis [Abstract]
Individually evaluated loans outstanding balance, net of a valuation allowance	2,400		7,300
Allowance for credit losses	1,500		1,000
Provision (recovery) for credit losses	807
Nonrecurring | Level 3 Inputs
Assets and Liabilities Measured at Fair Value on a Nonrecurring Basis [Abstract]
Individually evaluated loans	854		6,336
Carrying Amount
Assets and Liabilities Measured at Fair Value on a Nonrecurring Basis [Abstract]
Individually evaluated loans	10,687,661		10,695,349
Carrying Amount | Nonrecurring
Assets and Liabilities Measured at Fair Value on a Nonrecurring Basis [Abstract]
Individually evaluated loans	$ 854		$ 6,336