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Loans Held for Investment and Allowance for Credit Losses on Loans - Schedule of Portfolio Segments Weighted Average Life, and Measures the Allowance for Credit Losses (Detail) - ASC 326 [Member] | 12 Months Ended
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Dec. 31, 2023
Real Estate [Member] | Commercial Real Estate Owner Occupied [Member] |
Financing Receivable, Credit Quality Indicator [Line Items] |
Loan Segment, Life (in years) | 9 years
Real Estate [Member] | Commercial Real Estate Non-Owner Occupied [Member] |
Financing Receivable, Credit Quality Indicator [Line Items] |
Loan Segment, Life (in years) | 6 years
Real Estate [Member] | Construction and Development Less than 60 Months [Member] |
Financing Receivable, Credit Quality Indicator [Line Items] |
Loan Segment, Life (in years) | 3 years
Real Estate [Member] | Construction Residential Real Estate Less than 60 Months [Member] |
Financing Receivable, Credit Quality Indicator [Line Items] |
Loan Segment, Life (in years) | 2 years
Real Estate [Member] | Residential Real Estate First Lien [Member] |
Financing Receivable, Credit Quality Indicator [Line Items] |
Loan Segment, Life (in years) | 15 years
Real Estate [Member] | Residential Real Estate All Other [Member] |
Financing Receivable, Credit Quality Indicator [Line Items] |
Loan Segment, Life (in years) | 8 years
Real Estate [Member] | Agriculture [Member] |
Financing Receivable, Credit Quality Indicator [Line Items] |
Loan Segment, Life (in years) | 9 years
Commercial Non-real Estate [Member] |
Financing Receivable, Credit Quality Indicator [Line Items] |
Loan Segment, Life (in years) | 4 years
Consumer Non-real Estate [Member] |
Financing Receivable, Credit Quality Indicator [Line Items] |
Loan Segment, Life (in years) | 4 years
Oil and Gas [Member] |
Financing Receivable, Credit Quality Indicator [Line Items] |
Loan Segment, Life (in years) | 2 years

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- Definition 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. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479319/326-20-50-5 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 79 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479294/326-20-55-79 + Details
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