Loans Held for Investment and Allowance for Loan Losses - Schedule of Loans Modified and Considered Troubled Debt Restructurings (Detail) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2022 USD ($) Securityloan	Sep. 30, 2021 USD ($) Securityloan	Sep. 30, 2022 USD ($) Securityloan	Sep. 30, 2021 USD ($) Securityloan
Financing Receivable, Modifications [Line Items]
Number \| Securityloan		4		17
Pre-Modification Recorded Investment	$ 335	$ 105	$ 335	$ 2,255
Post-Modification Recorded Investment		$ 105		$ 2,255
Commercial [Member]
Financing Receivable, Modifications [Line Items]
Number \| Securityloan	1		1	4
Pre-Modification Recorded Investment	$ 205		$ 205	$ 361
Post-Modification Recorded Investment	$ 205		$ 205	$ 361
Commercial [Member] \| Commercial – C&I [Member]
Financing Receivable, Modifications [Line Items]
Number \| Securityloan	10		1	4
Pre-Modification Recorded Investment	$ 205		$ 205	$ 361
Post-Modification Recorded Investment	$ 205		$ 205	$ 361
Agriculture [Member]
Financing Receivable, Modifications [Line Items]
Number \| Securityloan				1
Pre-Modification Recorded Investment				$ 68
Post-Modification Recorded Investment				$ 68
Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Number \| Securityloan	1	2	1	9
Pre-Modification Recorded Investment	$ 130	$ 77	$ 130	$ 1,766
Post-Modification Recorded Investment	$ 130	$ 77	$ 130	$ 1,766
Real Estate [Member] \| Construction & Development [Member]
Financing Receivable, Modifications [Line Items]
Number \| Securityloan				1
Pre-Modification Recorded Investment				$ 200
Post-Modification Recorded Investment				$ 200
Real Estate [Member] \| Owner Occupied CRE [Member]
Financing Receivable, Modifications [Line Items]
Number \| Securityloan				3
Pre-Modification Recorded Investment				$ 1,047
Post-Modification Recorded Investment				$ 1,047
Real Estate [Member] \| Residential [Member]
Financing Receivable, Modifications [Line Items]
Number \| Securityloan	1	2	1	5
Pre-Modification Recorded Investment	$ 130	$ 77	$ 130	$ 519
Post-Modification Recorded Investment	$ 130	$ 77	$ 130	$ 519
Consumer [Member]
Financing Receivable, Modifications [Line Items]
Number \| Securityloan	2	2	2	3
Pre-Modification Recorded Investment	$ 335	$ 28	$ 335	$ 60
Post-Modification Recorded Investment	$ 335	$ 28	$ 335	$ 60
Consumer [Member] \| Auto [Member]
Financing Receivable, Modifications [Line Items]
Number \| Securityloan		1		2
Pre-Modification Recorded Investment		$ 19		$ 51
Post-Modification Recorded Investment		$ 19		$ 51
Consumer [Member] \| Non Auto [Member]
Financing Receivable, Modifications [Line Items]
Number \| Securityloan		1		1
Pre-Modification Recorded Investment		$ 9		$ 9
Post-Modification Recorded Investment		$ 9		$ 9

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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 https://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524

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