Organization and Basis of Presentation - Additional Information (Detail) $ in Millions		3 Months Ended
Mar. 17, 2021	Mar. 31, 2021 USD ($)
Organization And Basis Of Presentation [Line Items]
Stockholders equity note reverse stocks split conversion ratio	1.5
Stock split description	On March 17, 2021, the Company announced that its board of directors had approved a three-for-two stock split (“Stock Split”) effected in the form of a 50% stock dividend on its common stock outstanding paid on April 30, 2021 to shareholders of record as of April 20, 2021.
Percentage of stock dividend payable on stock split of common stock.	50.00%
Dividend, payment date	Apr. 30, 2021
Dividend, record date	Apr. 20, 2021
Correction of Prior Period Classification Error [Member]
Organization And Basis Of Presentation [Line Items]
Decrease in loans held for sale		$ 30.4
Increase in loans held for investment		$ 30.4

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Increase in loans held for investment.

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Percentage of stock dividend payable on stock split of common stock.

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Date the declared dividend will be paid, in CCYY-MM-DD format.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
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Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

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Description of the stock split arrangement. Also provide the retroactive effect given by a stock split that occurs after the balance date but before the release of financial statements.

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Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one.

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