FAIR VALUE OF FINANCIAL INSTRUMENTS - Assets and Liabilities Measured at Fair Value on a Recurring and Nonrecurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Financial Assets
Derivative assets	$ 122,132	$ 154,485
Financial Liabilities
Derivative liabilities	121,265	137,335
Certain individually evaluated loans
Individually evaluated loans	6,300
Recurring | Cash flow hedges
Financial Assets
Derivative assets	7,461	17,150
Recurring | Freestanding derivatives, net
Financial Assets
Derivative assets	114,671	137,335
Financial Liabilities
Derivative liabilities	114,671	137,335
Recurring | Fair value hedges
Financial Liabilities
Derivative liabilities	6,594
Recurring | Level 2 Inputs | Cash flow hedges
Financial Assets
Derivative assets	7,461	17,150
Recurring | Level 2 Inputs | Freestanding derivatives, net
Financial Assets
Derivative assets	114,671	137,335
Financial Liabilities
Derivative liabilities	114,671	137,335
Recurring | Level 2 Inputs | Fair value hedges
Financial Liabilities
Derivative liabilities	6,594
Nonrecurring | Level 3 Inputs
Certain individually evaluated loans
Individually evaluated loans	6,336	1,179
Carrying Amount
Certain individually evaluated loans
Individually evaluated loans	10,695,349	10,482,145
Carrying Amount | Nonrecurring
Certain individually evaluated loans
Individually evaluated loans	6,336	1,179
US Government Agencies Debt Securities [Member] | Recurring
Financial Assets
Securities available-for-sale:	9,371	227,256
US Government Agencies Debt Securities [Member] | Recurring | Level 2 Inputs
Financial Assets
Securities available-for-sale:	9,371	227,256
US Treasury Securities [Member] | Recurring
Financial Assets
Securities available-for-sale:	234,190	166,773
US Treasury Securities [Member] | Recurring | Level 2 Inputs
Financial Assets
Securities available-for-sale:	234,190	166,773
Corporate securities | Recurring
Financial Assets
Securities available-for-sale:	151,170	241,240
Corporate securities | Recurring | Level 2 Inputs
Financial Assets
Securities available-for-sale:	151,170	241,240
Pass-through mortgage-backed securities ("MBS") issued by government sponsored entities ("GSEs") | Recurring
Financial Assets
Marketable equity securities (Registered Mutual Funds)		281,339
Mortgage-backed securities	205,285
Pass-through mortgage-backed securities ("MBS") issued by government sponsored entities ("GSEs") | Recurring | Level 2 Inputs
Financial Assets
Marketable equity securities (Registered Mutual Funds)		281,339
Mortgage-backed securities	205,285
Agency collateralized mortgage obligations ("CMOs") | Recurring
Financial Assets
Securities available-for-sale:	259,415	33,979
Agency collateralized mortgage obligations ("CMOs") | Recurring | Level 2 Inputs
Financial Assets
Securities available-for-sale:	259,415	$ 33,979
State and municipal obligations. | Recurring
Financial Assets
Securities available-for-sale:	26,809
State and municipal obligations. | Recurring | Level 2 Inputs
Financial Assets
Securities available-for-sale:	$ 26,809