Loans Held for Investment and Allowance for Loan Losses - Non-Accrual Loans, Loans Still Accruing and Past Due 90 Days or More and Restructured Loans (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020
Receivables [Abstract]
Non-accrual loans	$ 39,333	$ 42,619	$ 39,226
Loans still accruing and past due 90 days or more	2	113	209
Troubled debt restructured loans still accruing	23	24	26
Total	$ 39,358	$ 42,756	$ 39,461

Amount of financing receivable modified as troubled debt restructuring.

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- Definition

Amount of financing receivable 90 days or more past due and still accruing.

+ References

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Reflects the carrying amount of loans deemed to be questionable as to collection on which no interest is continuing to be recognized.

+ References

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Amount, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement.

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