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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
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-Name Accounting Standards Codification
-Section 45
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LOANS HELD FOR INVESTMENT, NET - Collateral Dependent Loans (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Jun. 30, 2023	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Dec. 31, 2021
Financing Receivable, Allowance for Credit Loss [Line Items]
Total Loans	$ 10,850,611		$ 10,566,831
Allowance for credit losses	72,563		83,507
Real Estate Collateral Dependent \| Total real estate loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Total Loans	4,428		8,997
Allowance for credit losses	305		1,297
Business loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Total Loans	2,271,768		2,211,857
Allowance for credit losses	36,680	$ 39,700	47,029	$ 44,492	$ 45,128	$ 62,366
Business loans \| Real Estate Collateral Dependent
Financing Receivable, Allowance for Credit Loss [Line Items]
Total Loans	3,771		5,849
One-to-four family residential and cooperative/condominium apartment
Financing Receivable, Allowance for Credit Loss [Line Items]
Total Loans	892,869		773,321
Allowance for credit losses	7,206	6,419	5,969	5,058	4,514	5,932
Multifamily residential and residential mixed-use
Financing Receivable, Allowance for Credit Loss [Line Items]
Total Loans	4,102,024		4,026,826
Allowance for credit losses	7,567	8,190	8,360	8,054	7,003	7,816
Non-owner-occupied commercial real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Total Loans	3,374,281		3,317,485
Allowance for credit losses	18,430	18,440	20,153	20,507	18,707	2,131
Non-owner-occupied commercial real estate \| Total real estate loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Total Loans	3,374,281		3,317,485
Non-owner-occupied commercial real estate \| Real Estate Collateral Dependent
Financing Receivable, Allowance for Credit Loss [Line Items]
Total Loans			2,491
Allowance for credit losses			1,297
Acquisition, development, and construction ("ADC")
Financing Receivable, Allowance for Credit Loss [Line Items]
Total Loans	203,402		229,663
Allowance for credit losses	2,338	2,558		3,619	3,788
Acquisition, development, and construction ("ADC") \| Total real estate loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for credit losses	2,338		1,723	3,619		4,857
Acquisition, development, and construction ("ADC") \| Real Estate Collateral Dependent
Financing Receivable, Allowance for Credit Loss [Line Items]
Total Loans	657		657
Allowance for credit losses	305
Other Loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Total Loans	6,267		7,679
Allowance for credit losses	$ 342	$ 339	$ 273	$ 205	$ 286	$ 751