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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 | Jun. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | $ 43,536,716 | $ 42,609,028
Non-accrual with an ALL | 215,356 | 271,174
Non-accrual without an ALL | 42,059 | 37,990
Accrued interest receivable | $ 220,400 | $ 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) | $ (36,600) | $ (34,100)
Total commercial and industrial |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 23,098,344 | 22,331,129
Non-accrual with an ALL | 111,648 | 119,264
Non-accrual without an ALL | 17,661 | 37,990
Total commercial and industrial | Commercial, financial and agricultural |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 15,238,812 | 14,498,992
Non-accrual with an ALL | 100,571 | 98,145
Non-accrual without an ALL | 9,610 | 24,729
Total commercial and industrial | Owner-occupied |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 7,859,532 | 7,832,137
Non-accrual with an ALL | 11,077 | 21,119
Non-accrual without an ALL | 8,051 | 13,261
Total commercial real estate |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 12,139,690 | 12,014,619
Non-accrual with an ALL | 39,141 | 77,804
Non-accrual without an ALL | 22,122 | 0
Total commercial real estate | Investment properties |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 11,309,520 | 11,181,204
Non-accrual with an ALL | 35,401 | 74,030
Non-accrual without an ALL | 22,122 | 0
Total commercial real estate | 1-4 family properties |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 536,878 | 545,918
Non-accrual with an ALL | 2,386 | 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 | 293,292 | 287,497
Non-accrual with an ALL | 1,354 | 1,389
Non-accrual without an ALL | 0 | 0
Total consumer |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 8,298,682 | 8,263,280
Non-accrual with an ALL | 64,567 | 74,106
Non-accrual without an ALL | 2,276 | 0
Total consumer | Consumer mortgages |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 5,246,940 | 5,288,776
Non-accrual with an ALL | 41,849 | 50,834
Non-accrual without an ALL | 1,627 | 0
Total consumer | Home equity |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 1,852,884 | 1,831,287
Non-accrual with an ALL | 17,098 | 17,365
Non-accrual without an ALL | 615 | 0
Total consumer | Credit cards |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 194,630 | 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 | 1,004,228 | 957,346
Non-accrual with an ALL | 5,620 | 5,907
Non-accrual without an ALL | 34 | 0
Current |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 43,175,034 | 42,190,986
Current | Total commercial and industrial |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 22,910,880 | 22,106,891
Current | Total commercial and industrial | Commercial, financial and agricultural |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 15,113,723 | 14,352,839
Current | Total commercial and industrial | Owner-occupied |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 7,797,157 | 7,754,052
Current | Total commercial real estate |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 12,075,474 | 11,931,858
Current | Total commercial real estate | Investment properties |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 11,250,988 | 11,105,168
Current | Total commercial real estate | 1-4 family properties |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 533,156 | 541,897
Current | Total commercial real estate | Land and development |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 291,330 | 284,793
Current | Total consumer |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 8,188,680 | 8,152,237
Current | Total consumer | Consumer mortgages |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 5,192,882 | 5,228,580
Current | Total consumer | Home equity |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 1,815,612 | 1,800,614
Current | Total consumer | Credit cards |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 191,172 | 182,435
Current | Total consumer | Other consumer loans |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 989,014 | 940,608
Accruing 30-89 Days Past Due |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 64,202 | 60,286
Accruing 30-89 Days Past Due | Total commercial and industrial |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 19,978 | 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 | 12,810 | 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 | 7,168 | 7,700
Accruing 30-89 Days Past Due | Total commercial real estate |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 2,953 | 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 | 1,009 | 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 | 1,336 | 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 | 608 | 1,113
Accruing 30-89 Days Past Due | Total consumer |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 41,271 | 34,884
Accruing 30-89 Days Past Due | Total consumer | Consumer mortgages |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 10,582 | 9,362
Accruing 30-89 Days Past Due | Total consumer | Home equity |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 19,559 | 13,131
Accruing 30-89 Days Past Due | Total consumer | Credit cards |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 1,656 | 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 | 9,474 | 10,818
Accruing 90 Days or Greater Past Due |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 40,065 | 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 | 38,177 | 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 | 2,098 | 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 | 36,079 | 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 | 1,888 | 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 | 0 | 177
Accruing 90 Days or Greater Past Due | Total consumer | Credit cards |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 1,802 | 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 | 86 | 13
Total Accruing Past Due |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 104,267 | 108,878
Total Accruing Past Due | Total commercial and industrial |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 58,155 | 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 | 14,908 | 23,279
Total Accruing Past Due | Total commercial and industrial | Owner-occupied |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 43,247 | 43,705
Total Accruing Past Due | Total commercial real estate |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 2,953 | 4,957
Total Accruing Past Due | Total commercial real estate | Investment properties |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 1,009 | 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 | 1,336 | 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 | 608 | 1,315
Total Accruing Past Due | Total consumer |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 43,159 | 36,937
Total Accruing Past Due | Total consumer | Consumer mortgages |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 10,582 | 9,362
Total Accruing Past Due | Total consumer | Home equity |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 19,559 | 13,308
Total Accruing Past Due | Total consumer | Credit cards |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | 3,458 | 3,436
Total Accruing Past Due | Total consumer | Other consumer loans |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Loans, net of deferred fees and costs | $ 9,560 | $ 10,831

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