Loans Held for Investment and Allowance for Loan Losses - Schedule of Loans Modified and Considered Troubled Debt Restructurings (Detail) $ in Thousands	3 Months Ended
Mar. 31, 2021 USD ($) Securityloan
Financing Receivable, Modifications [Line Items]
Number \| Securityloan	5
Pre-Modification Recorded Investment	$ 846
Post-Modification Recorded Investment	$ 846
Commercial [Member]
Financing Receivable, Modifications [Line Items]
Number \| Securityloan	2
Pre-Modification Recorded Investment	$ 149
Post-Modification Recorded Investment	$ 149
Commercial [Member] \| Commercial – C&I [Member]
Financing Receivable, Modifications [Line Items]
Number \| Securityloan	2
Pre-Modification Recorded Investment	$ 149
Post-Modification Recorded Investment	$ 149
Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Number \| Securityloan	3
Pre-Modification Recorded Investment	$ 697
Post-Modification Recorded Investment	$ 697
Real Estate [Member] \| Owner Occupied CRE [Member]
Financing Receivable, Modifications [Line Items]
Number \| Securityloan	1
Pre-Modification Recorded Investment	$ 500
Post-Modification Recorded Investment	$ 500
Real Estate [Member] \| Residential [Member]
Financing Receivable, Modifications [Line Items]
Number \| Securityloan	2
Pre-Modification Recorded Investment	$ 197
Post-Modification Recorded Investment	$ 197

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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Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524

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Amount, after troubled debt restructuring, of modified financing receivable.

+ References

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- Definition

Amount, before troubled debt restructuring, of financing receivable to be modified.

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