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Loans and Allowance for Credit Losses - Outstanding Balances of Loan (Detail) - USD ($) $ in Thousands | 9 Months Ended |
--- | --- | ---
Sep. 30, 2025 | Dec. 31, 2024
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable, before Allowance for Credit Loss | $ 9,688,288 | $ 8,983,754
Default Status Of TDRs After Number Of Days Past Due | 90 days |
Time and Demand Loans |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable, before Allowance for Credit Loss | $ 1,251,980 | 1,133,595
Commercial Credit Cards |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable, before Allowance for Credit Loss | 11,709 | 11,718
Senior Lien |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable, before Allowance for Credit Loss | 1,664,891 | 1,670,547
Junior Lien |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable, before Allowance for Credit Loss | 717,834 | 671,156
Multifamily |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable, before Allowance for Credit Loss | 656,182 | 597,145
Nonowner Occupied Commercial Real Estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable, before Allowance for Credit Loss | 1,944,990 | 1,804,950
Owner Occupied Commercial Real Estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable, before Allowance for Credit Loss | 807,629 | 722,609
Automobiles |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable, before Allowance for Credit Loss | 1,370,551 | 1,280,645
Consumer Credit Cards |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable, before Allowance for Credit Loss | 9,359 | 9,865
Other Consumer Loans |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable, before Allowance for Credit Loss | 62,385 | 65,464
Equipment Finance |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable, before Allowance for Credit Loss | 634,398 | 427,320
Time and Demand Loans Other |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable, before Allowance for Credit Loss | 110,938 | 105,356
Construction Other |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable, before Allowance for Credit Loss | 403,548 | 475,367
Construction Residential |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable, before Allowance for Credit Loss | 41,894 | 8,017
Commercial, financial, agricultural and other [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable, before Allowance for Credit Loss | 2,009,025 | 1,677,989
Commercial, financial, agricultural and other [Member] | Time and Demand Loans |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable, before Allowance for Credit Loss | 1,251,980 | 1,133,595
Commercial, financial, agricultural and other [Member] | Commercial Credit Cards |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable, before Allowance for Credit Loss | 11,709 | 11,718
Commercial, financial, agricultural and other [Member] | Equipment Finance |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable, before Allowance for Credit Loss | 634,398 | 427,320
Commercial, financial, agricultural and other [Member] | Time and Demand Loans Other |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable, before Allowance for Credit Loss | 110,938 | 105,356
Real estate construction [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable, before Allowance for Credit Loss | 445,442 | 483,384
Real estate construction [Member] | Construction Other |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable, before Allowance for Credit Loss | 403,548 | 475,367
Real estate construction [Member] | Construction Residential |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable, before Allowance for Credit Loss | 41,894 | 8,017
Residential real estate [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable, before Allowance for Credit Loss | 2,382,725 | 2,341,703
Residential real estate [Member] | Senior Lien |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable, before Allowance for Credit Loss | 1,664,891 | 1,670,547
Residential real estate [Member] | Junior Lien |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable, before Allowance for Credit Loss | 717,834 | 671,156
Commercial Real Estate [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable, before Allowance for Credit Loss | 3,408,801 | 3,124,704
Commercial Real Estate [Member] | Multifamily |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable, before Allowance for Credit Loss | 656,182 | 597,145
Commercial Real Estate [Member] | Nonowner Occupied Commercial Real Estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable, before Allowance for Credit Loss | 1,944,990 | 1,804,950
Commercial Real Estate [Member] | Owner Occupied Commercial Real Estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable, before Allowance for Credit Loss | 807,629 | 722,609
Loans to individuals [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable, before Allowance for Credit Loss | 1,442,295 | 1,355,974
Loans to individuals [Member] | Automobiles |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable, before Allowance for Credit Loss | 1,370,551 | 1,280,645
Loans to individuals [Member] | Consumer Credit Cards |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable, before Allowance for Credit Loss | 9,359 | 9,865
Loans to individuals [Member] | Other Consumer Loans |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable, before Allowance for Credit Loss | $ 62,385 | $ 65,464

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