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Loans and Allowance for Loan Losses - Schedule of Current, Accruing Past Due, and Non-Accrual Loans by Portfolio Class (Details) - USD ($) $ in Thousands | Sep. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | $ 43,753,234 | $ 42,609,028
Non-accrual with an ALL | 201,924 | 271,174
Non-accrual without an ALL | 7,403 | 37,990
Accrued interest receivable | $ 216,300 | $ 217,100
Financing receivable, accrued interest, after allowance for credit loss, statement of financial position [extensible enumeration] | Other assets | Other assets
Deferred loan costs (fees) | $ (41,000) | $ (34,100)
Total commercial and industrial |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 23,228,969 | 22,331,129
Non-accrual with an ALL | 93,702 | 119,264
Non-accrual without an ALL | 5,170 | 37,990
Total commercial and industrial | Commercial, financial and agricultural |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 15,360,223 | 14,498,992
Non-accrual with an ALL | 84,282 | 98,145
Non-accrual without an ALL | 4,813 | 24,729
Total commercial and industrial | Owner-occupied |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 7,868,746 | 7,832,137
Non-accrual with an ALL | 9,420 | 21,119
Non-accrual without an ALL | 357 | 13,261
Total commercial real estate |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 12,269,740 | 12,014,619
Non-accrual with an ALL | 37,624 | 77,804
Non-accrual without an ALL | 1,043 | 0
Total commercial real estate | Investment properties |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 11,462,107 | 11,181,204
Non-accrual with an ALL | 34,768 | 74,030
Non-accrual without an ALL | 1,043 | 0
Total commercial real estate | 1-4 family properties |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 548,327 | 545,918
Non-accrual with an ALL | 2,144 | 2,385
Non-accrual without an ALL | 0 | 0
Total commercial real estate | Land and development |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 259,306 | 287,497
Non-accrual with an ALL | 712 | 1,389
Non-accrual without an ALL | 0 | 0
Total consumer |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 8,254,525 | 8,263,280
Non-accrual with an ALL | 70,598 | 74,106
Non-accrual without an ALL | 1,190 | 0
Total consumer | Consumer mortgages |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 5,237,683 | 5,288,776
Non-accrual with an ALL | 44,414 | 50,834
Non-accrual without an ALL | 579 | 0
Total consumer | Home equity |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 1,842,126 | 1,831,287
Non-accrual with an ALL | 20,189 | 17,365
Non-accrual without an ALL | 611 | 0
Total consumer | Credit cards |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 176,367 | 185,871
Non-accrual with an ALL | 0 | 0
Non-accrual without an ALL | 0 | 0
Total consumer | Other consumer loans |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 998,349 | 957,346
Non-accrual with an ALL | 5,995 | 5,907
Non-accrual without an ALL | 0 | 0
Current |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 43,499,724 | 42,190,986
Current | Total commercial and industrial |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 23,117,245 | 22,106,891
Current | Total commercial and industrial | Commercial, financial and agricultural |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 15,263,978 | 14,352,839
Current | Total commercial and industrial | Owner-occupied |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 7,853,267 | 7,754,052
Current | Total commercial real estate |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 12,228,497 | 11,931,858
Current | Total commercial real estate | Investment properties |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 11,424,644 | 11,105,168
Current | Total commercial real estate | 1-4 family properties |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 545,699 | 541,897
Current | Total commercial real estate | Land and development |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 258,154 | 284,793
Current | Total consumer |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 8,153,982 | 8,152,237
Current | Total consumer | Consumer mortgages |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 5,186,944 | 5,228,580
Current | Total consumer | Home equity |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 1,811,056 | 1,800,614
Current | Total consumer | Credit cards |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 173,199 | 182,435
Current | Total consumer | Other consumer loans |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 982,783 | 940,608
Accruing 30-89 Days Past Due |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 40,382 | 60,286
Accruing 30-89 Days Past Due | Total commercial and industrial |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 10,857 | 20,647
Accruing 30-89 Days Past Due | Total commercial and industrial | Commercial, financial and agricultural |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 5,155 | 12,947
Accruing 30-89 Days Past Due | Total commercial and industrial | Owner-occupied |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 5,702 | 7,700
Accruing 30-89 Days Past Due | Total commercial real estate |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 2,576 | 4,755
Accruing 30-89 Days Past Due | Total commercial real estate | Investment properties |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 1,652 | 2,006
Accruing 30-89 Days Past Due | Total commercial real estate | 1-4 family properties |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 484 | 1,636
Accruing 30-89 Days Past Due | Total commercial real estate | Land and development |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 440 | 1,113
Accruing 30-89 Days Past Due | Total consumer |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 26,949 | 34,884
Accruing 30-89 Days Past Due | Total consumer | Consumer mortgages |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 5,746 | 9,362
Accruing 30-89 Days Past Due | Total consumer | Home equity |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 10,106 | 13,131
Accruing 30-89 Days Past Due | Total consumer | Credit cards |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 1,526 | 1,573
Accruing 30-89 Days Past Due | Total consumer | Other consumer loans |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 9,571 | 10,818
Accruing 90 Days or Greater Past Due |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 3,801 | 48,592
Accruing 90 Days or Greater Past Due | Total commercial and industrial |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 1,995 | 46,337
Accruing 90 Days or Greater Past Due | Total commercial and industrial | Commercial, financial and agricultural |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 1,995 | 10,332
Accruing 90 Days or Greater Past Due | Total commercial and industrial | Owner-occupied |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 0 | 36,005
Accruing 90 Days or Greater Past Due | Total commercial real estate |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 0 | 202
Accruing 90 Days or Greater Past Due | Total commercial real estate | Investment properties |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 0 | 0
Accruing 90 Days or Greater Past Due | Total commercial real estate | 1-4 family properties |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 0 | 0
Accruing 90 Days or Greater Past Due | Total commercial real estate | Land and development |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 0 | 202
Accruing 90 Days or Greater Past Due | Total consumer |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 1,806 | 2,053
Accruing 90 Days or Greater Past Due | Total consumer | Consumer mortgages |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 0 | 0
Accruing 90 Days or Greater Past Due | Total consumer | Home equity |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 164 | 177
Accruing 90 Days or Greater Past Due | Total consumer | Credit cards |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 1,642 | 1,863
Accruing 90 Days or Greater Past Due | Total consumer | Other consumer loans |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 0 | 13
Total Accruing Past Due |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 44,183 | 108,878
Total Accruing Past Due | Total commercial and industrial |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 12,852 | 66,984
Total Accruing Past Due | Total commercial and industrial | Commercial, financial and agricultural |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 7,150 | 23,279
Total Accruing Past Due | Total commercial and industrial | Owner-occupied |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 5,702 | 43,705
Total Accruing Past Due | Total commercial real estate |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 2,576 | 4,957
Total Accruing Past Due | Total commercial real estate | Investment properties |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 1,652 | 2,006
Total Accruing Past Due | Total commercial real estate | 1-4 family properties |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 484 | 1,636
Total Accruing Past Due | Total commercial real estate | Land and development |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 440 | 1,315
Total Accruing Past Due | Total consumer |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 28,755 | 36,937
Total Accruing Past Due | Total consumer | Consumer mortgages |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 5,746 | 9,362
Total Accruing Past Due | Total consumer | Home equity |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 10,270 | 13,308
Total Accruing Past Due | Total consumer | Credit cards |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 3,168 | 3,436
Total Accruing Past Due | Total consumer | Other consumer loans |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | $ 9,571 | $ 10,831

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