FAIR VALUE OF FINANCIAL INSTRUMENTS - Assets and Liabilities Measured at Fair Value on a Recurring and Nonrecurring Basis (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Financial Assets
Derivative assets	$ 147,740	$ 154,485
Financial Liabilities
Derivative liabilities	131,130	137,335
Recurring | Cash flow hedges
Financial Assets
Derivative assets	16,611	17,150
Recurring | Freestanding derivatives, net
Financial Assets
Derivative assets	131,130	137,335
Financial Liabilities
Derivative liabilities	131,130	137,335
Recurring | Level 2 Inputs | Cash flow hedges
Financial Assets
Derivative assets	16,611	17,150
Recurring | Level 2 Inputs | Freestanding derivatives, net
Financial Assets
Derivative assets	131,130	137,335
Financial Liabilities
Derivative liabilities	131,130	137,335
Nonrecurring | Level 3 Inputs
Certain individually evaluated loans
Individually evaluated loans	352	1,179
Carrying Amount
Certain individually evaluated loans
Individually evaluated loans	10,800,417	10,482,145
Carrying Amount | Nonrecurring
Certain individually evaluated loans
Individually evaluated loans	352	1,179
Agency Notes | Recurring
Financial Assets
Securities available-for-sale:	9,145
Agency Notes | Recurring | Level 2 Inputs
Financial Assets
Securities available-for-sale:	9,145
Treasury Securities | Recurring
Financial Assets
Securities available-for-sale:	228,607	227,256
Treasury Securities | Recurring | Level 2 Inputs
Financial Assets
Securities available-for-sale:	228,607	227,256
Corporate Securities | Recurring
Financial Assets
Securities available-for-sale:	139,553	166,773
Corporate Securities | Recurring | Level 2 Inputs
Financial Assets
Securities available-for-sale:	139,553	166,773
Pass-through mortgage-backed securities ("MBS") issued by government sponsored entities ("GSEs") | Recurring
Financial Assets
Mortgage-backed securities	222,584	241,240
Pass-through mortgage-backed securities ("MBS") issued by government sponsored entities ("GSEs") | Recurring | Level 2 Inputs
Financial Assets
Mortgage-backed securities	222,584	241,240
Agency collateralized mortgage obligations ("CMOs") | Recurring
Financial Assets
Securities available-for-sale:	265,673	281,339
Agency collateralized mortgage obligations ("CMOs") | Recurring | Level 2 Inputs
Financial Assets
Securities available-for-sale:	265,673	281,339
State and municipal obligations. | Recurring
Financial Assets
Securities available-for-sale:	29,294	33,979
State and municipal obligations. | Recurring | Level 2 Inputs
Financial Assets
Securities available-for-sale:	$ 29,294	$ 33,979