LOANS HELD FOR INVESTMENT, NET - Loan Categories (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Loans held for investment, net:
Loans held for investment, net of fees and costs	$ 9,660,907	$ 9,244,661
Allowance for loan losses	(79,426)	(83,853)
Total loans held for investment, net	$ 9,581,481	9,160,808
Small Business Administration ("SBA") Paycheck Protection Program ("PPP") [Member]
Loans held for investment, net:
Loan and leases carry guarantee rate	100.00%
Total real estate loans
Loans held for investment, net:
Loans held for investment, net of fees and costs	$ 8,689,230	8,294,204
One-to-four family residential and cooperative/condominium apartment
Loans held for investment, net:
Loans held for investment, net of fees and costs	691,586	669,282
Multifamily residential and residential mixed-use
Loans held for investment, net:
Loans held for investment, net of fees and costs	3,654,164	3,356,346
Commercial real estate ("CRE")
Loans held for investment, net:
Loans held for investment, net of fees and costs	4,091,372	3,945,948
Acquisition, development, and construction
Loans held for investment, net:
Loans held for investment, net of fees and costs	252,108	322,628
Commercial and Industrial ("C&I") Loans
Loans held for investment, net:
Loans held for investment, net of fees and costs	960,888	933,559
Commercial and Industrial ("C&I") Loans \| Small Business Administration ("SBA") Paycheck Protection Program ("PPP") [Member]
Loans held for investment, net:
Loans held for investment, net of fees and costs	18,900	66,000
Other Loans
Loans held for investment, net:
Loans held for investment, net of fees and costs	$ 10,789	$ 16,898

The percentage of reference loans carry guarantee rate Small Business Administration ("SBA") Paycheck Protection Program ("PPP") loans.

No definition available.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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