ADVANCES FROM THE FEDERAL HOME LOAN BANK (FHLB) - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Federal Home Loan Bank, Advances [Line Items]
Additional capacity on credit facility based on collateral pledged	$ 644,200
Fixed-rate advances from FHLB	675,000	$ 200,000
Average balance during the year	$ 179,500	$ 354,100
FHLB for collateral purposes, haircut percent	14.00%	17.00%
Estimated value of U.S. government-sponsored agencies' obligations and U.S. agencies MBS pledged as collateral amount	$ 238,100
Loans held for investment	11,552,825	$ 11,060,658
Asset Pledged as Collateral [Member]
Federal Home Loan Bank, Advances [Line Items]
Loans held for investment	4,300,000	4,100,000
Maximum [Member]
Federal Home Loan Bank, Advances [Line Items]
Maximum aggregate balance of advances from the FHLB outstanding at any month-end during period	675,000	440,000
Short-term Debt [Member]
Federal Home Loan Bank, Advances [Line Items]
Fixed-rate advances from FHLB	475,000	0
Long-term Debt [Member]
Federal Home Loan Bank, Advances [Line Items]
Fixed-rate advances from FHLB	200,000	200,000
Federal Home Loan Bank Advances [Member] \| Asset Pledged as Collateral [Member]
Federal Home Loan Bank, Advances [Line Items]
Loans held for investment	1,800,000	1,800,000
Loans pledged including collateral	$ 1,300,000	$ 1,400,000

Estimated value of U.S. government-sponsored agencies obligations and U.S. agencies MBS pledged as collateral amount

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- Definition

FHLB For Collateral Purposes, Haircut Percent

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The estimated value (including the collateral discount) as of the balance sheet date of loans that have been pledged as collateral for borrowings.

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The calculated average balance outstanding for the year for all Federal Home Loan Bank advances as of the Balance Sheet date.

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The maximum balance outstanding at any month end during the period as of the Balance Sheet date.

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Par amount of advances made and reported by Federal Home Loan Bank (FHLBank) with fixed interest rate.

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Amount of advances or credit lines available from the Federal Home Loan Bank (FHLB).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amortized cost, before allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease.

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