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Loans Past Due Status (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 30, 2025 | Sep. 30, 2025 | Dec. 31, 2024
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | $ 30,951,964 | $ 30,951,964 | $ 29,768,586
Financing Receivable, Nonaccrual | 106,179 | 106,179 | 123,260
Nonaccrual Loans, Current Portion | $ 38,000 | $ 38,000 | $ 52,400
Percent of current nonaccrual loans | 36.00% | 36.00% | 42.00%
Financing Receivable, Nonaccrual, Interest Income | $ 0 | $ 0 | $ 0
Financing Receivable, Nonaccrual, No Allowance | 14,800 | 14,800 | 23,800
Commercial and Industrial Sector |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 11,567,651 | 11,567,651 | 10,573,741
Financing Receivable, Nonaccrual | 12,802 | 12,802 | 19,084
Commercial Real Estate Owner Occupied Portfolio [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 1,149,939 | 1,149,939 | 1,143,741
Financing Receivable, Nonaccrual | 203 | 203 | 1,501
Commercial And Business Lending [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 12,717,590 | 12,717,590 | 11,717,483
Financing Receivable, Nonaccrual | 13,006 | 13,006 | 20,585
Commercial Real Estate Investor Portfolio Segment [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 5,369,441 | 5,369,441 | 5,227,975
Financing Receivable, Nonaccrual | 7,333 | 7,333 | 16,705
Construction Loans [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 1,958,766 | 1,958,766 | 1,982,632
Financing Receivable, Nonaccrual | 145 | 145 | 30
Commercial Real Estate Portfolio Segment [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 7,328,207 | 7,328,207 | 7,210,607
Financing Receivable, Nonaccrual | 7,478 | 7,478 | 16,735
Commercial Portfolio Segment [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 20,045,797 | 20,045,797 | 18,928,090
Financing Receivable, Nonaccrual | 20,484 | 20,484 | 37,320
Residential Mortgage [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 6,858,285 | 6,858,285 | 7,047,541
Financing Receivable, Nonaccrual | 69,093 | 69,093 | 70,038
Automobile Loan [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 3,041,644 | 3,041,644 | 2,810,220
Financing Receivable, Nonaccrual | 8,218 | 8,218 | 7,402
Home Equity Line of Credit [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 698,112 | 698,112 | 664,252
Financing Receivable, Nonaccrual | 8,299 | 8,299 | 8,378
Other Consumer [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 308,126 | 308,126 | 318,483
Financing Receivable, Nonaccrual | 85 | 85 | 122
Consumer Loan [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 10,906,167 | 10,906,167 | 10,840,496
Financing Receivable, Nonaccrual | 85,696 | 85,696 | 85,941
Financial Asset, Not Past Due [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 30,794,122 | 30,794,122 | 29,565,335
Financial Asset, Not Past Due [Member] | Commercial and Industrial Sector |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 11,553,383 | 11,553,383 | 10,552,756
Financial Asset, Not Past Due [Member] | Commercial Real Estate Owner Occupied Portfolio [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 1,149,736 | 1,149,736 | 1,140,607
Financial Asset, Not Past Due [Member] | Commercial And Business Lending [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 12,703,119 | 12,703,119 | 11,693,363
Financial Asset, Not Past Due [Member] | Commercial Real Estate Investor Portfolio Segment [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 5,347,918 | 5,347,918 | 5,174,879
Financial Asset, Not Past Due [Member] | Construction Loans [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 1,958,600 | 1,958,600 | 1,982,581
Financial Asset, Not Past Due [Member] | Commercial Real Estate Portfolio Segment [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 7,306,518 | 7,306,518 | 7,157,460
Financial Asset, Not Past Due [Member] | Commercial Portfolio Segment [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 20,009,637 | 20,009,637 | 18,850,823
Financial Asset, Not Past Due [Member] | Residential Mortgage [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 6,776,508 | 6,776,508 | 6,962,610
Financial Asset, Not Past Due [Member] | Automobile Loan [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 3,019,413 | 3,019,413 | 2,787,967
Financial Asset, Not Past Due [Member] | Home Equity Line of Credit [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 685,548 | 685,548 | 651,248
Financial Asset, Not Past Due [Member] | Other Consumer [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 303,016 | 303,016 | 312,687
Financial Asset, Not Past Due [Member] | Consumer Loan [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 10,784,484 | 10,784,484 | 10,714,512
Financial Asset, 30 to 59 Days Past Due [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 43,970 | 43,970 | 40,961
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial and Industrial Sector |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 517 | 517 | 899
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Real Estate Owner Occupied Portfolio [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 0 | 0 | 1,533
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial And Business Lending [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 517 | 517 | 2,432
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Real Estate Investor Portfolio Segment [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 13,168 | 13,168 | 5,117
Financial Asset, 30 to 59 Days Past Due [Member] | Construction Loans [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 21 | 21 | 21
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Real Estate Portfolio Segment [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 13,189 | 13,189 | 5,138
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Portfolio Segment [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 13,706 | 13,706 | 7,570
Financial Asset, 30 to 59 Days Past Due [Member] | Residential Mortgage [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 12,667 | 12,667 | 14,731
Financial Asset, 30 to 59 Days Past Due [Member] | Automobile Loan [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 11,997 | 11,997 | 12,588
Financial Asset, 30 to 59 Days Past Due [Member] | Home Equity Line of Credit [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 4,059 | 4,059 | 4,181
Financial Asset, 30 to 59 Days Past Due [Member] | Other Consumer [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 1,540 | 1,540 | 1,892
Financial Asset, 30 to 59 Days Past Due [Member] | Consumer Loan [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 30,264 | 30,264 | 33,391
Financial Asset, 60 to 89 Days Past Due [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 5,002 | 5,002 | 35,841
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial and Industrial Sector |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 554 | 554 | 361
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Real Estate Owner Occupied Portfolio [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 0 | 0 | 101
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial And Business Lending [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 554 | 554 | 462
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Real Estate Investor Portfolio Segment [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 1,022 | 1,022 | 31,274
Financial Asset, 60 to 89 Days Past Due [Member] | Construction Loans [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 0 | 0 | 0
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Real Estate Portfolio Segment [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 1,022 | 1,022 | 31,274
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Portfolio Segment [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 1,576 | 1,576 | 31,736
Financial Asset, 60 to 89 Days Past Due [Member] | Residential Mortgage [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 16 | 16 | 162
Financial Asset, 60 to 89 Days Past Due [Member] | Automobile Loan [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 2,016 | 2,016 | 2,262
Financial Asset, 60 to 89 Days Past Due [Member] | Home Equity Line of Credit [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 206 | 206 | 445
Financial Asset, 60 to 89 Days Past Due [Member] | Other Consumer [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 1,188 | 1,188 | 1,236
Financial Asset, 60 to 89 Days Past Due [Member] | Consumer Loan [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 3,426 | 3,426 | 4,105
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 2,692 | 2,692 | 3,189
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial and Industrial Sector |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 395 | 395 | 642
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Real Estate Owner Occupied Portfolio [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 0 | 0 | 0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial And Business Lending [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 395 | 395 | 642
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Real Estate Investor Portfolio Segment [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 0 | 0 | 0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Construction Loans [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 0 | 0 | 0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Real Estate Portfolio Segment [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 0 | 0 | 0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Portfolio Segment [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 395 | 395 | 642
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Residential Mortgage [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 0 | 0 | 0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Automobile Loan [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 0 | 0 | 0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Home Equity Line of Credit [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 0 | 0 | 0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Other Consumer [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 2,297 | 2,297 | 2,547
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Consumer Loan [Member] |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | $ 2,297 | $ 2,297 | $ 2,547

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