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LOANS HELD FOR INVESTMENT, NET - Loans by Category Modified as TDRs (Details) $ in Thousands	3 Months Ended	12 Months Ended
	Jun. 30, 2023 USD ($) item	Dec. 31, 2022 USD ($) loan	Mar. 31, 2023 USD ($)	Jun. 30, 2022 USD ($)	Mar. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for credit losses	$ 75,646	$ 83,507
Number of Loans	0	12
Pre-Modification Outstanding Recorded Investment		$ 37,463
Post-Modification Outstanding Recorded Investment		37,467
TDRs
Financing Receivable, Allowance for Credit Loss [Line Items]
Commitments to lend any additional funds on restructured loans		0
Modifications recorded investment		22,100
Allowance for credit losses		9,100
Business Loan Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for credit losses	$ 39,700	$ 47,029	$ 43,879	$ 45,128	$ 43,728	$ 62,366
Number of Loans \| loan		7
Pre-Modification Outstanding Recorded Investment		$ 21,934
Post-Modification Outstanding Recorded Investment		21,938
One-to-four family residential and cooperative/condominium apartment
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for credit losses	6,419	$ 5,969	6,012	4,514	4,528	5,932
Number of Loans \| loan		2
Pre-Modification Outstanding Recorded Investment		$ 762
Post-Modification Outstanding Recorded Investment		762
Non-owner Occupied Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for credit losses	18,440	$ 20,153	18,076	18,707	19,180	2,131
Number of Loans \| loan		1
Pre-Modification Outstanding Recorded Investment		$ 991
Post-Modification Outstanding Recorded Investment		$ 991
Acquisition, development, and construction ("ADC")
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for credit losses	2,558		2,515	3,788	4,758
Number of Loans \| loan		1
Pre-Modification Outstanding Recorded Investment		$ 13,500
Post-Modification Outstanding Recorded Investment		13,500
Other Loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for credit losses	$ 339	$ 273	$ 240	$ 286	$ 360	$ 751
Number of Loans \| loan		1
Pre-Modification Outstanding Recorded Investment		$ 276
Post-Modification Outstanding Recorded Investment		$ 276