FAIR VALUE OF FINANCIAL INSTRUMENTS - Financial Instruments Not Measured at Fair Value (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024
Financial Assets
Securities held-to-maturity	$ 558,786	$ 552,277
Loans held for sale	2,527	22,625
Reported value measurement
Financial Assets
Cash and due from banks	1,030,702	1,283,571
Securities held-to-maturity	631,334	637,339
Loans held for sale	2,527	22,625
Loans held for investment, net	10,776,322	10,775,608
Accrued interest receivable	56,044	55,970
Financial Liabilities
Savings, money market and checking accounts	10,494,856	10,617,060
CDs	1,121,068	1,069,081
FHLBNY Advances	508,000	608,000
Subordinated debt, net	272,370	272,325
Other short-term borrowings		50,000
Accrued interest payable	9,302	8,586
Estimate of Fair Value Measurement
Financial Assets
Cash and due from banks	1,030,702	1,283,571
Securities held-to-maturity	558,786	552,277
Loans held for sale	2,527	22,625
Loans held for investment, net	10,419,587	10,354,366
Accrued interest receivable	56,044	55,970
Financial Liabilities
Savings, money market and checking accounts	10,494,856	10,617,060
CDs	1,118,156	1,066,630
FHLBNY Advances	510,485	608,908
Subordinated debt, net	256,150	257,464
Other short-term borrowings		50,000
Accrued interest payable	9,302	8,586
Level 1 | Estimate of Fair Value Measurement
Financial Assets
Cash and due from banks	1,030,702	1,283,571
Financial Liabilities
Savings, money market and checking accounts	10,494,856	10,617,060
Other short-term borrowings		50,000
Level 2 | Estimate of Fair Value Measurement
Financial Assets
Securities held-to-maturity	558,786	552,277
Accrued interest receivable	6,438	6,676
Financial Liabilities
CDs	1,118,156	1,066,630
FHLBNY Advances	510,485	608,908
Subordinated debt, net	256,150	257,464
Accrued interest payable	9,302	8,586
Level 3 | Estimate of Fair Value Measurement
Financial Assets
Loans held for sale	2,527	22,625
Loans held for investment, net	10,419,587	10,354,366
Accrued interest receivable	$ 49,606	$ 49,294