Loans Held for Investment and Allowance for Credit Losses on Loans - Purchased Credit Deteriorated Loans (Detail) - Loans Acquired with Deteriorated Credit Quality [Member] - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021
Financing Receivable Allowance For Credit Losses [Line Items]
Purchase price of loans at acquisition	$ 661	$ 39,284
Allowance for credit losses at acquisition	71	8,299
Par value of acquired loans at acquisition	$ 732	$ 47,583

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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- Definition

Amount of allowance for credit loss at acquisition date of financing receivable purchased with credit deterioration.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 19
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919265-210447

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- Definition

Amount at par value of financing receivable purchased with credit deterioration.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 19
-Subparagraph (d)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919265-210447

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- Definition

Amount at purchase price of financing receivable purchased with credit deterioration.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 19
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919265-210447

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