v3.26.1
Loans and Allowance for Credit Losses - Age Analysis of Past Due Loans by Segment (Detail) - USD ($)
$ in Thousands
Jun. 30, 2026
Dec. 31, 2025
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss $ 9,467,229 $ 9,508,039
Time and Demand Loans    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 1,151,708 1,226,054
Commercial Credit Cards    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 12,135 11,408
Senior Lien    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 1,605,497 1,631,019
Junior Lien    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 762,669 729,266
Multifamily    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 636,826 594,790
Nonowner Occupied Commercial Real Estate    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 1,690,230 1,834,016
Owner Occupied Commercial Real Estate    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 756,718 753,303
Automobiles    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 1,390,894 1,387,195
Consumer Credit Cards    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 8,819 9,496
Other Consumer Loans    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 57,523 61,179
Construction Residential    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 30,413 47,250
Construction Other    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 456,253 415,536
Time and Demand Loans Other    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 122,790 114,262
Equipment Finance    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 784,754 693,265
Commercial, financial, agricultural and other [Member]    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 2,071,387 2,044,989
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 1,151,708 1,226,054
Commercial, financial, agricultural and other [Member] | Commercial Credit Cards    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 12,135 11,408
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 122,790 114,262
Commercial, financial, agricultural and other [Member] | Equipment Finance    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 784,754 693,265
Real estate construction [Member]    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 486,666 462,786
Real estate construction [Member] | Construction Residential    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 30,413 47,250
Real estate construction [Member] | Construction Other    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 456,253 415,536
Residential real estate [Member]    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 2,368,166 2,360,285
Residential real estate [Member] | Senior Lien    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 1,605,497 1,631,019
Residential real estate [Member] | Junior Lien    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 762,669 729,266
Commercial Real Estate [Member]    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 3,083,774 3,182,109
Commercial Real Estate [Member] | Multifamily    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 636,826 594,790
Commercial Real Estate [Member] | Nonowner Occupied Commercial Real Estate    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 1,690,230 1,834,016
Commercial Real Estate [Member] | Owner Occupied Commercial Real Estate    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 756,718 753,303
Loans to individuals [Member]    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 1,457,236 1,457,870
Loans to individuals [Member] | Automobiles    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 1,390,894 1,387,195
Loans to individuals [Member] | Consumer Credit Cards    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 8,819 9,496
Loans to individuals [Member] | Other Consumer Loans    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 57,523 61,179
Financial Asset, 30 to 59 Days Past Due [Member]    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 26,974 22,032
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial, financial, agricultural and other [Member]    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 4,085 5,127
Financial Asset, 30 to 59 Days Past Due [Member] | 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 1,425 2,666
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial, financial, agricultural and other [Member] | Commercial Credit Cards    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 45 75
Financial Asset, 30 to 59 Days Past Due [Member] | 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 1 4
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial, financial, agricultural and other [Member] | Equipment Finance    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 2,614 2,382
Financial Asset, 30 to 59 Days Past Due [Member] | Real estate construction [Member]    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 1,703 0
Financial Asset, 30 to 59 Days Past Due [Member] | Real estate construction [Member] | Construction Residential    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 785 0
Financial Asset, 30 to 59 Days Past Due [Member] | Real estate construction [Member] | Construction Other    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 918 0
Financial Asset, 30 to 59 Days Past Due [Member] | Residential real estate [Member]    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 7,061 8,197
Financial Asset, 30 to 59 Days Past Due [Member] | Residential real estate [Member] | Senior Lien    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 3,786 5,054
Financial Asset, 30 to 59 Days Past Due [Member] | Residential real estate [Member] | Junior Lien    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 3,275 3,143
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Real Estate [Member]    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 7,849 1,975
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Real Estate [Member] | Multifamily    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 0 417
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Real Estate [Member] | Nonowner Occupied Commercial Real Estate    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 1,163 534
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Real Estate [Member] | Owner Occupied Commercial Real Estate    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 6,686 1,024
Financial Asset, 30 to 59 Days Past Due [Member] | Loans to individuals [Member]    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 6,276 6,733
Financial Asset, 30 to 59 Days Past Due [Member] | Loans to individuals [Member] | Automobiles    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 5,906 6,262
Financial Asset, 30 to 59 Days Past Due [Member] | Loans to individuals [Member] | Consumer Credit Cards    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 42 50
Financial Asset, 30 to 59 Days Past Due [Member] | Loans to individuals [Member] | Other Consumer Loans    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 328 421
Financial Asset, 60 to 89 Days Past Due [Member]    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 16,258 13,760
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial, financial, agricultural and other [Member]    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 10,375 595
Financial Asset, 60 to 89 Days Past Due [Member] | 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 9,164 125
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial, financial, agricultural and other [Member] | Commercial Credit Cards    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 31 32
Financial Asset, 60 to 89 Days Past Due [Member] | 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 0 0
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial, financial, agricultural and other [Member] | Equipment Finance    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 1,180 438
Financial Asset, 60 to 89 Days Past Due [Member] | Real estate construction [Member]    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 0 0
Financial Asset, 60 to 89 Days Past Due [Member] | Real estate construction [Member] | Construction Residential    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 0 0
Financial Asset, 60 to 89 Days Past Due [Member] | Real estate construction [Member] | Construction Other    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 0 0
Financial Asset, 60 to 89 Days Past Due [Member] | Residential real estate [Member]    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 3,192 1,870
Financial Asset, 60 to 89 Days Past Due [Member] | Residential real estate [Member] | Senior Lien    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 2,017 1,456
Financial Asset, 60 to 89 Days Past Due [Member] | Residential real estate [Member] | Junior Lien    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 1,175 414
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Real Estate [Member]    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 1,389 10,070
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Real Estate [Member] | Multifamily    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 0 0
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Real Estate [Member] | Nonowner Occupied Commercial Real Estate    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 0 10,070
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Real Estate [Member] | Owner Occupied Commercial Real Estate    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 1,389 0
Financial Asset, 60 to 89 Days Past Due [Member] | Loans to individuals [Member]    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 1,302 1,225
Financial Asset, 60 to 89 Days Past Due [Member] | Loans to individuals [Member] | Automobiles    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 1,082 1,022
Financial Asset, 60 to 89 Days Past Due [Member] | Loans to individuals [Member] | Consumer Credit Cards    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 43 35
Financial Asset, 60 to 89 Days Past Due [Member] | Loans to individuals [Member] | Other Consumer Loans    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 177 168
Non Accrual Loans [Member]    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 81,640 91,756
Non Accrual Loans [Member] | Commercial, financial, agricultural and other [Member]    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 40,682 46,618
Non Accrual Loans [Member] | 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 38,004 45,288
Non Accrual Loans [Member] | Commercial, financial, agricultural and other [Member] | Commercial Credit Cards    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 0 0
Non Accrual Loans [Member] | 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 0 0
Non Accrual Loans [Member] | Commercial, financial, agricultural and other [Member] | Equipment Finance    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 2,678 1,330
Non Accrual Loans [Member] | Real estate construction [Member]    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 0 1,475
Non Accrual Loans [Member] | Real estate construction [Member] | Construction Residential    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 0 0
Non Accrual Loans [Member] | Real estate construction [Member] | Construction Other    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 0 1,475
Non Accrual Loans [Member] | Residential real estate [Member]    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 15,329 13,019
Non Accrual Loans [Member] | Residential real estate [Member] | Senior Lien    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 10,459 8,364
Non Accrual Loans [Member] | Residential real estate [Member] | Junior Lien    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 4,870 4,655
Non Accrual Loans [Member] | Commercial Real Estate [Member]    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 25,622 30,612
Non Accrual Loans [Member] | Commercial Real Estate [Member] | Multifamily    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 10,846 10
Non Accrual Loans [Member] | Commercial Real Estate [Member] | Nonowner Occupied Commercial Real Estate    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 6,389 14,156
Non Accrual Loans [Member] | Commercial Real Estate [Member] | Owner Occupied Commercial Real Estate    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 8,387 16,446
Non Accrual Loans [Member] | Loans to individuals [Member]    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 7 32
Non Accrual Loans [Member] | Loans to individuals [Member] | Automobiles    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 5 30
Non Accrual Loans [Member] | Loans to individuals [Member] | Consumer Credit Cards    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 0 0
Non Accrual Loans [Member] | Loans to individuals [Member] | Other Consumer Loans    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 2 2
Financial Asset, Equal to or Greater than 90 Days Past Due [Member]    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 3,218 1,288
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial, financial, agricultural and other [Member]    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 1,675 217
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | 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 1,675 107
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial, financial, agricultural and other [Member] | Commercial Credit Cards    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 0 0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | 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 0 0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial, financial, agricultural and other [Member] | Equipment Finance    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 0 110
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Real estate construction [Member]    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 0 0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Real estate construction [Member] | Construction Residential    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 0 0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Real estate construction [Member] | Construction Other    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 0 0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Residential real estate [Member]    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 1,149 581
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Residential real estate [Member] | Senior Lien    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 982 317
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Residential real estate [Member] | Junior Lien    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 167 264
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Real Estate [Member]    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 0 0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Real Estate [Member] | Multifamily    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 0 0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Real Estate [Member] | Nonowner Occupied Commercial Real Estate    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 0 0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Real Estate [Member] | Owner Occupied Commercial Real Estate    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 0 0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Loans to individuals [Member]    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 394 490
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Loans to individuals [Member] | Automobiles    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 213 168
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Loans to individuals [Member] | Consumer Credit Cards    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 0 0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Loans to individuals [Member] | Other Consumer Loans    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 181 322
Financial Asset, Past Due    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 128,090 128,836
Financial Asset, Past Due | Commercial, financial, agricultural and other [Member]    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 56,817 52,557
Financial Asset, Past Due | 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 50,268 48,186
Financial Asset, Past Due | Commercial, financial, agricultural and other [Member] | Commercial Credit Cards    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 76 107
Financial Asset, Past Due | 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 1 4
Financial Asset, Past Due | Commercial, financial, agricultural and other [Member] | Equipment Finance    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 6,472 4,260
Financial Asset, Past Due | Real estate construction [Member]    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 1,703 1,475
Financial Asset, Past Due | Real estate construction [Member] | Construction Residential    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 785 0
Financial Asset, Past Due | Real estate construction [Member] | Construction Other    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 918 1,475
Financial Asset, Past Due | Residential real estate [Member]    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 26,731 23,667
Financial Asset, Past Due | Residential real estate [Member] | Senior Lien    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 17,244 15,191
Financial Asset, Past Due | Residential real estate [Member] | Junior Lien    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 9,487 8,476
Financial Asset, Past Due | Commercial Real Estate [Member]    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 34,860 42,657
Financial Asset, Past Due | Commercial Real Estate [Member] | Multifamily    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 10,846 427
Financial Asset, Past Due | Commercial Real Estate [Member] | Nonowner Occupied Commercial Real Estate    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 7,552 24,760
Financial Asset, Past Due | Commercial Real Estate [Member] | Owner Occupied Commercial Real Estate    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 16,462 17,470
Financial Asset, Past Due | Loans to individuals [Member]    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 7,979 8,480
Financial Asset, Past Due | Loans to individuals [Member] | Automobiles    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 7,206 7,482
Financial Asset, Past Due | Loans to individuals [Member] | Consumer Credit Cards    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 85 85
Financial Asset, Past Due | Loans to individuals [Member] | Other Consumer Loans    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 688 913
Financial Asset, Not Past Due    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 9,339,139 9,379,203
Financial Asset, Not Past Due | Commercial, financial, agricultural and other [Member]    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 2,014,570 1,992,432
Financial Asset, Not Past Due | 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 1,101,440 1,177,868
Financial Asset, Not Past Due | Commercial, financial, agricultural and other [Member] | Commercial Credit Cards    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 12,059 11,301
Financial Asset, Not Past Due | 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 122,789 114,258
Financial Asset, Not Past Due | Commercial, financial, agricultural and other [Member] | Equipment Finance    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 778,282 689,005
Financial Asset, Not Past Due | Real estate construction [Member]    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 484,963 461,311
Financial Asset, Not Past Due | Real estate construction [Member] | Construction Residential    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 29,628 47,250
Financial Asset, Not Past Due | Real estate construction [Member] | Construction Other    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 455,335 414,061
Financial Asset, Not Past Due | Residential real estate [Member]    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 2,341,435 2,336,618
Financial Asset, Not Past Due | Residential real estate [Member] | Senior Lien    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 1,588,253 1,615,828
Financial Asset, Not Past Due | Residential real estate [Member] | Junior Lien    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 753,182 720,790
Financial Asset, Not Past Due | Commercial Real Estate [Member]    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 3,048,914 3,139,452
Financial Asset, Not Past Due | Commercial Real Estate [Member] | Multifamily    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 625,980 594,363
Financial Asset, Not Past Due | Commercial Real Estate [Member] | Nonowner Occupied Commercial Real Estate    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 1,682,678 1,809,256
Financial Asset, Not Past Due | Commercial Real Estate [Member] | Owner Occupied Commercial Real Estate    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 740,256 735,833
Financial Asset, Not Past Due | Loans to individuals [Member]    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 1,449,257 1,449,390
Financial Asset, Not Past Due | Loans to individuals [Member] | Automobiles    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 1,383,688 1,379,713
Financial Asset, Not Past Due | Loans to individuals [Member] | Consumer Credit Cards    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss 8,734 9,411
Financial Asset, Not Past Due | Loans to individuals [Member] | Other Consumer Loans    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Financing Receivable, before Allowance for Credit Loss $ 56,835 $ 60,266