FAIR VALUE OF FINANCIAL INSTRUMENTS - Financial Instruments Not Measured at Fair Value (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Financial Assets [Abstract]
Securities held-to-maturity	$ 505,759	$ 177,354
Loans held for investment, net	1,200
Carrying Amount
Financial Assets [Abstract]
Cash and due from banks	169,297	393,722
Securities held-to-maturity	585,798	179,309
Loans held for investment, net	10,482,145	9,158,908
Accrued interest receivable	48,561	40,149
Financial Liabilities [Abstract]
Savings, money market and checking accounts	9,139,043	9,605,731
Certificates of Deposits ("CDs")	1,115,364	853,242
FHLBNY Advances	1,131,000	25,000
Subordinated debt, net	200,283	197,096
Other short-term borrowings	1,360	1,862
Accrued interest payable	5,323	870
Fair Value
Financial Assets [Abstract]
Cash and due from banks	169,297	393,722
Securities held-to-maturity	505,759	177,354
Loans held for investment, net	10,005,121	9,169,872
Accrued interest receivable	48,561	40,149
Financial Liabilities [Abstract]
Savings, money market and checking accounts	9,139,043	9,605,731
Certificates of Deposits ("CDs")	1,096,808	857,342
FHLBNY Advances	1,131,217	25,014
Subordinated debt, net	180,583	202,334
Other short-term borrowings	1,360	1,862
Accrued interest payable	5,323	870
Level 1 Inputs | Fair Value
Financial Assets [Abstract]
Cash and due from banks	169,297	393,722
Financial Liabilities [Abstract]
Savings, money market and checking accounts	9,139,043	9,605,731
Other short-term borrowings	1,360	1,862
Level 2 Inputs | Fair Value
Financial Assets [Abstract]
Securities held-to-maturity	505,759	177,354
Accrued interest receivable	6,105	4,481
Financial Liabilities [Abstract]
Certificates of Deposits ("CDs")	1,096,808	857,342
FHLBNY Advances	1,131,217	25,014
Subordinated debt, net	180,583	202,334
Accrued interest payable	5,323	870
Level 3 Inputs | Fair Value
Financial Assets [Abstract]
Loans held for investment, net	10,005,121	9,169,872
Accrued interest receivable	$ 42,456	$ 35,668