Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

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Reflects the carrying amount of loans and leases for which agreements to acquire or dispose exist.

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LOANS HELD FOR INVESTMENT, NET - TDRs (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2022 USD ($) loan	Mar. 31, 2023 USD ($)	Mar. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for credit losses	$ 83,507	$ 78,335
Number of Loans \| loan	12
Pre-Modification Outstanding Recorded Investment	$ 37,463
Post-Modification Outstanding Recorded Investment	37,467
TDRs
Financing Receivable, Allowance for Credit Loss [Line Items]
Modifications recorded investment	22,100
Commitments to lend additional amounts	0
Allowance for credit losses	9,100
One-to-four family residential and cooperative/condominium apartment
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for credit losses	$ 5,969	6,012	$ 4,528	$ 5,932
Number of Loans \| loan	2
Pre-Modification Outstanding Recorded Investment	$ 762
Post-Modification Outstanding Recorded Investment	762
Commercial real estate ("CRE")
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for credit losses	$ 27,329	24,478	28,645	29,166
Number of Loans \| loan	1
Pre-Modification Outstanding Recorded Investment	$ 991
Post-Modification Outstanding Recorded Investment	991
Acquisition, development, and construction
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for credit losses	$ 1,723	2,515	4,758	4,857
Number of Loans \| loan	1
Pre-Modification Outstanding Recorded Investment	$ 13,500
Post-Modification Outstanding Recorded Investment	13,500
Commercial and Industrial ("C&I") Loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for credit losses	$ 39,853	37,477	34,263	35,331
Number of Loans \| loan	7
Pre-Modification Outstanding Recorded Investment	$ 21,934
Post-Modification Outstanding Recorded Investment	21,938
Other Loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for credit losses	$ 273	$ 240	$ 360	$ 751
Number of Loans \| loan	1
Pre-Modification Outstanding Recorded Investment	$ 276
Post-Modification Outstanding Recorded Investment	$ 276