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Segment Reporting - Schedule of Financing Receivables by Segment (Details) $ in Thousands | Sep. 30, 2025 USD ($) employee | Dec. 31, 2024 USD ($) employee
--- | --- | ---
Segment Reporting Information [Line Items] |  |
Loans, net of deferred fees and costs | $ 43,753,234 | $ 42,609,028
Deposits | $ 50,003,729 | $ 51,095,359
Full-time equivalent employees | employee | 4,847 | 4,696
Operating Segments | Wholesale Banking |  |
Segment Reporting Information [Line Items] |  |
Loans, net of deferred fees and costs | $ 25,821,429 | $ 24,677,119
Deposits | $ 14,319,619 | $ 15,207,166
Full-time equivalent employees | employee | 355 | 336
Operating Segments | Community Banking |  |
Segment Reporting Information [Line Items] |  |
Loans, net of deferred fees and costs | $ 8,075,467 | $ 7,921,182
Deposits | $ 11,126,772 | $ 10,877,394
Full-time equivalent employees | employee | 552 | 533
Operating Segments | Consumer Banking |  |
Segment Reporting Information [Line Items] |  |
Loans, net of deferred fees and costs | $ 2,603,853 | $ 2,776,305
Deposits | $ 17,585,811 | $ 18,365,142
Full-time equivalent employees | employee | 1,524 | 1,491
Operating Segments | Financial Management Services |  |
Segment Reporting Information [Line Items] |  |
Loans, net of deferred fees and costs | $ 5,210,585 | $ 5,263,474
Deposits | $ 1,298,703 | $ 1,109,270
Full-time equivalent employees | employee | 553 | 565
Treasury and Corporate Other |  |
Segment Reporting Information [Line Items] |  |
Loans, net of deferred fees and costs | $ 2,041,900 | $ 1,970,948
Deposits | $ 5,672,824 | $ 5,536,387
Full-time equivalent employees | employee | 1,863 | 1,771

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