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Loans and Leases (Composition of the Loans and Leases Outstanding By Credit Quality Indicator) (Details) - USD ($) $ in Thousands | Sep. 30, 2020 | Dec. 31, 2019
--- | --- | ---
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans | $ 32,349,266 | $ 28,322,780
Past due loans | 249,119 | 272,770
Current loans | 32,596,025 | 28,608,726
Commercial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans | 22,613,932 | 18,552,002
Commercial | Mortgage |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 12,282,635
Commercial | Other commercial real estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 542,028
Commercial | Commercial and industrial and leases |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans | 4,797,344 | 4,403,792
Commercial | Other |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 310,093
Commercial | Construction and land development |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans | 1,054,186 | 1,013,454
Consumer |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans | 9,735,334 | 9,770,778
Consumer | Construction and land development |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans | 347,850 | 357,385
Consumer | Revolving mortgage |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 2,339,072
Consumer | Consumer |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 1,780,404
Non-PCI Loans | Commercial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 18,552,002
Past due loans |  | 74,146
Current loans |  | 18,477,856
Non-PCI Loans | Commercial | Mortgage |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 12,282,635
Past due loans | 35,261 | 37,482
Current loans | 10,648,561 | 12,245,153
Non-PCI Loans | Commercial | Other commercial real estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 542,028
Past due loans | 23,906 | 1,890
Current loans | 2,941,998 | 540,138
Non-PCI Loans | Commercial | Commercial and industrial and leases |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 4,403,792
Past due loans | 16,183 | 28,143
Current loans | 4,781,161 | 4,375,649
Non-PCI Loans | Commercial | Other |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 310,093
Past due loans | 84,712 | 588
Current loans | 22,529,220 | 309,505
Non-PCI Loans | Commercial | Construction and land development |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 1,013,454
Past due loans | 9,362 | 6,043
Current loans | 1,044,824 | 1,007,411
Non-PCI Loans | Commercial | Pass |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 18,157,655
Non-PCI Loans | Commercial | Pass | Mortgage |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 12,050,799
Non-PCI Loans | Commercial | Pass | Other commercial real estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 536,682
Non-PCI Loans | Commercial | Pass | Commercial and industrial and leases |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 4,256,456
Non-PCI Loans | Commercial | Pass | Other |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 308,796
Non-PCI Loans | Commercial | Pass | Construction and land development |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 1,004,922
Non-PCI Loans | Commercial | Special Mention |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 166,866
Non-PCI Loans | Commercial | Special Mention | Mortgage |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 115,164
Non-PCI Loans | Commercial | Special Mention | Other commercial real estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 3,899
Non-PCI Loans | Commercial | Special Mention | Commercial and industrial and leases |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 44,604
Non-PCI Loans | Commercial | Special Mention | Other |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 622
Non-PCI Loans | Commercial | Special Mention | Construction and land development |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 2,577
Non-PCI Loans | Commercial | Substandard |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 158,897
Non-PCI Loans | Commercial | Substandard | Mortgage |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 116,672
Non-PCI Loans | Commercial | Substandard | Other commercial real estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 1,447
Non-PCI Loans | Commercial | Substandard | Commercial and industrial and leases |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 34,148
Non-PCI Loans | Commercial | Substandard | Other |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 675
Non-PCI Loans | Commercial | Substandard | Construction and land development |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 5,955
Non-PCI Loans | Commercial | Doubtful |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 3
Non-PCI Loans | Commercial | Doubtful | Mortgage |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 0
Non-PCI Loans | Commercial | Doubtful | Other commercial real estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 0
Non-PCI Loans | Commercial | Doubtful | Commercial and industrial and leases |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 3
Non-PCI Loans | Commercial | Doubtful | Other |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 0
Non-PCI Loans | Commercial | Doubtful | Construction and land development |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 0
Non-PCI Loans | Commercial | Ungraded |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 68,581
Non-PCI Loans | Commercial | Ungraded | Mortgage |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 0
Non-PCI Loans | Commercial | Ungraded | Other commercial real estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 0
Non-PCI Loans | Commercial | Ungraded | Commercial and industrial and leases |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 68,581
Non-PCI Loans | Commercial | Ungraded | Other |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 0
Non-PCI Loans | Commercial | Ungraded | Construction and land development |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 0
Non-PCI Loans | Consumer |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 9,770,778
Past due loans | 112,470 | 132,389
Current loans | 9,622,864 | 9,638,389
Non-PCI Loans | Consumer | Mortgage |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 5,293,917
Past due loans |  | 88,537
Current loans |  | 5,205,380
Non-PCI Loans | Consumer | Construction and land development |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 357,385
Past due loans | 6,214 | 2,992
Current loans | 1,227,982 | 354,393
Non-PCI Loans | Consumer | Revolving mortgage |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 2,339,072
Past due loans | 1,235 | 23,062
Current loans | 346,615 | 2,316,010
Non-PCI Loans | Consumer | Consumer |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 1,780,404
Past due loans | 7,281 | 17,798
Current loans | 536,855 | 1,762,606
PCD Loans |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Past due loans | 51,937 | 66,235
Current loans | 443,941 | 492,481
PCD Loans | Commercial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 284,329
PCD Loans | Commercial | Pass |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 148,412
PCD Loans | Commercial | Special Mention |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 44,290
PCD Loans | Commercial | Substandard |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 87,970
PCD Loans | Commercial | Doubtful |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 3,657
PCD Loans | Commercial | Ungraded |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 0
PCD Loans | Consumer |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-PCI loans |  | 274,387
Current loans |  | 240,995
30 to 59 Days past due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Past due loans | 121,823 | 136,220
30 to 59 Days past due | Non-PCI Loans | Commercial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Past due loans |  | 42,716
30 to 59 Days past due | Non-PCI Loans | Commercial | Mortgage |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Past due loans | 23,354 | 20,389
30 to 59 Days past due | Non-PCI Loans | Commercial | Other commercial real estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Past due loans | 9,854 | 861
30 to 59 Days past due | Non-PCI Loans | Commercial | Commercial and industrial and leases |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Past due loans | 8,401 | 18,269
30 to 59 Days past due | Non-PCI Loans | Commercial | Other |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Past due loans | 49,469 | 51
30 to 59 Days past due | Non-PCI Loans | Commercial | Construction and land development |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Past due loans | 7,860 | 3,146
30 to 59 Days past due | Non-PCI Loans | Consumer |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Past due loans | 56,056 | 67,026
30 to 59 Days past due | Non-PCI Loans | Consumer | Mortgage |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Past due loans |  | 45,839
30 to 59 Days past due | Non-PCI Loans | Consumer | Construction and land development |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Past due loans | 4,245 | 977
30 to 59 Days past due | Non-PCI Loans | Consumer | Revolving mortgage |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Past due loans | 923 | 9,729
30 to 59 Days past due | Non-PCI Loans | Consumer | Consumer |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Past due loans | 4,490 | 10,481
30 to 59 Days past due | PCD Loans |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Past due loans | 16,298 | 26,478
30 to 59 Days past due | PCD Loans | Consumer |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Past due loans |  | 13,764
60 to 89 Days past due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Past due loans | 29,490 | 51,058
60 to 89 Days past due | Non-PCI Loans | Commercial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Past due loans |  | 14,553
60 to 89 Days past due | Non-PCI Loans | Commercial | Mortgage |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Past due loans | 5,212 | 8,774
60 to 89 Days past due | Non-PCI Loans | Commercial | Other commercial real estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Past due loans | 7,381 | 331
60 to 89 Days past due | Non-PCI Loans | Commercial | Commercial and industrial and leases |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Past due loans | 3,920 | 4,842
60 to 89 Days past due | Non-PCI Loans | Commercial | Other |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Past due loans | 16,513 | 411
60 to 89 Days past due | Non-PCI Loans | Commercial | Construction and land development |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Past due loans | 0 | 195
60 to 89 Days past due | Non-PCI Loans | Consumer |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Past due loans | 9,776 | 25,721
60 to 89 Days past due | Non-PCI Loans | Consumer | Mortgage |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Past due loans |  | 18,289
60 to 89 Days past due | Non-PCI Loans | Consumer | Construction and land development |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Past due loans | 1,059 | 218
60 to 89 Days past due | Non-PCI Loans | Consumer | Revolving mortgage |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Past due loans | 0 | 3,468
60 to 89 Days past due | Non-PCI Loans | Consumer | Consumer |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Past due loans | 1,324 | 3,746
60 to 89 Days past due | PCD Loans |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Past due loans | 3,201 | 10,784
60 to 89 Days past due | PCD Loans | Consumer |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Past due loans |  | 5,608
90 Days or greater |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Past due loans | 97,806 | 85,492
90 Days or greater | Non-PCI Loans | Commercial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Past due loans |  | 16,877
90 Days or greater | Non-PCI Loans | Commercial | Mortgage |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Past due loans | 6,695 | 8,319
90 Days or greater | Non-PCI Loans | Commercial | Other commercial real estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Past due loans | 6,671 | 698
90 Days or greater | Non-PCI Loans | Commercial | Commercial and industrial and leases |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Past due loans | 3,862 | 5,032
90 Days or greater | Non-PCI Loans | Commercial | Other |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Past due loans | 18,730 | 126
90 Days or greater | Non-PCI Loans | Commercial | Construction and land development |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Past due loans | 1,502 | 2,702
90 Days or greater | Non-PCI Loans | Consumer |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Past due loans | 46,638 | 39,642
90 Days or greater | Non-PCI Loans | Consumer | Mortgage |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Past due loans |  | 24,409
90 Days or greater | Non-PCI Loans | Consumer | Construction and land development |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Past due loans | 910 | 1,797
90 Days or greater | Non-PCI Loans | Consumer | Revolving mortgage |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Past due loans | 312 | 9,865
90 Days or greater | Non-PCI Loans | Consumer | Consumer |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Past due loans | 1,467 | 3,571
90 Days or greater | PCD Loans |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Past due loans | $ 32,438 | 28,973
90 Days or greater | PCD Loans | Consumer |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Past due loans |  | $ 14,020

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