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

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.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph c
-Publisher SEC

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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
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 19
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-19

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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
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 19
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-19

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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
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 19
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-19

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