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Fair Value Accounting - Schedule of Carrying and Estimated Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands | Sep. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Financial assets |  |
Investment securities held to maturity | $ 2,450,885 | $ 2,581,469
Investment securities available for sale | 7,575,468 | 7,551,018
Loans held for sale | 147,811 | 90,111
Financial liabilities |  |
Non-interest-bearing deposits | 11,053,423 | 11,596,119
Total deposits | 50,003,729 | 51,095,359
Federal funds purchased, securities sold under repurchase agreements, and other short-term borrowings | 62,467 | 131,728
Long-term debt | 3,008,195 | 1,733,109
Derivatives Not Designated as Hedging Instruments |  |
Financial liabilities |  |
Estimated fair value of derivative liabilities | 120,958 | 201,917
Visa derivative | Derivatives Not Designated as Hedging Instruments |  |
Financial liabilities |  |
Estimated fair value of derivative liabilities | 2,964 | 64
Level 1 |  |
Financial assets |  |
Total cash, cash equivalents, and restricted cash | 2,274,207 | 2,993,987
Trading securities | 2,004 | 0
Investment securities held to maturity | 0 | 0
Investment securities available for sale | 1,221,154 | 1,212,742
Loans held for sale | 0 | 0
Other investments | 0 | 0
Mutual funds and mutual funds held in rabbi trusts | 72,883 | 63,371
Loans, net | 0 | 0
FRB and FHLB stock | 0 | 0
Derivative assets | 0 | 0
Financial liabilities |  |
Non-interest-bearing deposits | 0 | 0
Non-time interest-bearing deposits | 0 | 0
Time deposits | 0 | 0
Total deposits | 0 | 0
Federal funds purchased, securities sold under repurchase agreements, and other short-term borrowings | 62,467 | 131,728
Long-term debt | 0 | 0
Mutual funds held in rabbi trusts | 57,339 | 48,351
Derivative liabilities | 0 | 0
Level 2 |  |
Financial assets |  |
Total cash, cash equivalents, and restricted cash | 0 | 0
Trading securities | 19,185 | 9,713
Investment securities held to maturity | 2,466,265 | 2,524,525
Investment securities available for sale | 6,354,314 | 6,338,276
Loans held for sale | 41,083 | 33,448
Other investments | 0 | 0
Mutual funds and mutual funds held in rabbi trusts | 0 | 0
Loans, net | 0 | 0
FRB and FHLB stock | 240,959 | 164,374
Derivative assets | 85,822 | 83,895
Financial liabilities |  |
Non-interest-bearing deposits | 11,053,423 | 11,596,119
Non-time interest-bearing deposits | 29,949,544 | 29,883,378
Time deposits | 8,977,638 | 9,587,417
Total deposits | 49,980,605 | 51,066,914
Federal funds purchased, securities sold under repurchase agreements, and other short-term borrowings | 0 | 0
Long-term debt | 3,051,093 | 1,748,723
Mutual funds held in rabbi trusts | 0 | 0
Derivative liabilities | 117,994 | 216,325
Level 3 |  |
Financial assets |  |
Total cash, cash equivalents, and restricted cash | 0 | 0
Trading securities | 0 | 0
Investment securities held to maturity | 0 | 0
Investment securities available for sale | 0 | 0
Loans held for sale | 106,372 | 56,453
Other investments | 18,012 | 14,831
Mutual funds and mutual funds held in rabbi trusts | 0 | 0
Loans, net | 42,497,996 | 41,014,425
FRB and FHLB stock | 0 | 0
Derivative assets | 0 | 0
Financial liabilities |  |
Non-interest-bearing deposits | 0 | 0
Non-time interest-bearing deposits | 0 | 0
Time deposits | 0 | 0
Total deposits | 0 | 0
Federal funds purchased, securities sold under repurchase agreements, and other short-term borrowings | 0 | 0
Long-term debt | 0 | 0
Mutual funds held in rabbi trusts | 0 | 0
Derivative liabilities | 0 | 0
Carrying Value |  |
Financial assets |  |
Total cash, cash equivalents, and restricted cash | 2,274,207 | 2,993,987
Trading securities | 21,189 | 9,713
Investment securities held to maturity | 2,450,885 | 2,581,469
Investment securities available for sale | 7,575,468 | 7,551,018
Loans held for sale | 147,811 | 90,111
Other investments | 18,012 | 14,831
Mutual funds and mutual funds held in rabbi trusts | 72,883 | 63,371
Loans, net | 43,283,713 | 42,122,183
FRB and FHLB stock | 240,959 | 164,374
Derivative assets | 85,822 | 83,895
Financial liabilities |  |
Non-interest-bearing deposits | 11,053,423 | 11,596,119
Non-time interest-bearing deposits | 29,949,544 | 29,883,378
Time deposits | 9,000,762 | 9,615,862
Total deposits | 50,003,729 | 51,095,359
Federal funds purchased, securities sold under repurchase agreements, and other short-term borrowings | 62,467 | 131,728
Long-term debt | 3,008,195 | 1,733,109
Mutual funds held in rabbi trusts | 57,339 | 48,351
Derivative liabilities | 117,994 | 216,325
Fair Value |  |
Financial assets |  |
Total cash, cash equivalents, and restricted cash | 2,274,207 | 2,993,987
Trading securities | 21,189 | 9,713
Investment securities held to maturity | 2,466,265 | 2,524,525
Investment securities available for sale | 7,575,468 | 7,551,018
Loans held for sale | 147,455 | 89,901
Other investments | 18,012 | 14,831
Mutual funds and mutual funds held in rabbi trusts | 72,883 | 63,371
Loans, net | 42,497,996 | 41,014,425
FRB and FHLB stock | 240,959 | 164,374
Derivative assets | 85,822 | 83,895
Financial liabilities |  |
Non-interest-bearing deposits | 11,053,423 | 11,596,119
Non-time interest-bearing deposits | 29,949,544 | 29,883,378
Time deposits | 8,977,638 | 9,587,417
Total deposits | 49,980,605 | 51,066,914
Federal funds purchased, securities sold under repurchase agreements, and other short-term borrowings | 62,467 | 131,728
Long-term debt | 3,051,093 | 1,748,723
Mutual funds held in rabbi trusts | 57,339 | 48,351
Derivative liabilities | $ 117,994 | $ 216,325

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