LOANS HELD FOR INVESTMENT - Corporation's TDR Activity (Parenthetical) (Detail) - TDR [Member] - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Financing Receivable Modifications [Line Items]
Payoff	$ 8,132	$ 103,566	$ 26,926	$ 125,932
Commercial Portfolio Segment [Member] \| Mortgage Receivable [Member]
Financing Receivable Modifications [Line Items]
Payoff	$ 92,400		$ 92,400

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.

No definition available.

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