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Fair Value Accounting - Schedule of Carrying and Estimated Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands | Jun. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Financial assets |  |
Investment securities held to maturity | $ 2,502,639 | $ 2,581,469
Investment securities available for sale | 7,798,824 | 7,551,018
Loans held for sale | 153,037 | 90,111
Financial liabilities |  |
Non-interest-bearing deposits | 11,658,129 | 11,596,119
Total deposits | 49,925,007 | 51,095,359
Federal funds purchased, securities sold under repurchase agreements, and other short-term borrowings | 85,327 | 131,728
Long-term debt | 3,909,478 | 1,733,109
Derivatives Not Designated as Hedging Instruments |  |
Financial liabilities |  |
Estimated fair value of derivative liabilities | 134,690 | 201,917
Visa derivative | Derivatives Not Designated as Hedging Instruments |  |
Financial liabilities |  |
Estimated fair value of derivative liabilities | 62 | 64
Level 1 |  |
Financial assets |  |
Total cash, cash equivalents, and restricted cash | 2,852,316 | 2,993,987
Trading securities | 4,000 | 0
Investment securities held to maturity | 0 | 0
Investment securities available for sale | 1,240,926 | 1,212,742
Loans held for sale | 0 | 0
Other investments | 0 | 0
Mutual funds and mutual funds held in rabbi trusts | 69,686 | 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 | 85,327 | 131,728
Long-term debt | 0 | 0
Mutual funds held in rabbi trusts | 54,318 | 48,351
Derivative liabilities | 0 | 0
Level 2 |  |
Financial assets |  |
Total cash, cash equivalents, and restricted cash | 0 | 0
Trading securities | 11,475 | 9,713
Investment securities held to maturity | 2,476,289 | 2,524,525
Investment securities available for sale | 6,557,898 | 6,338,276
Loans held for sale | 45,136 | 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 | 266,855 | 164,374
Derivative assets | 82,664 | 83,895
Financial liabilities |  |
Non-interest-bearing deposits | 11,658,129 | 11,596,119
Non-time interest-bearing deposits | 29,727,720 | 29,883,378
Time deposits | 8,503,962 | 9,587,417
Total deposits | 49,889,811 | 51,066,914
Federal funds purchased, securities sold under repurchase agreements, and other short-term borrowings | 0 | 0
Long-term debt | 3,923,662 | 1,748,723
Mutual funds held in rabbi trusts | 0 | 0
Derivative liabilities | 134,644 | 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 | 107,504 | 56,453
Other investments | 16,899 | 14,831
Mutual funds and mutual funds held in rabbi trusts | 0 | 0
Loans, net | 42,231,633 | 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 | 2,852,316 | 2,993,987
Trading securities | 15,475 | 9,713
Investment securities held to maturity | 2,502,639 | 2,581,469
Investment securities available for sale | 7,798,824 | 7,551,018
Loans held for sale |  | 90,111
Other investments | 16,899 | 14,831
Mutual funds and mutual funds held in rabbi trusts | 69,686 | 63,371
Loans, net | 43,071,885 | 42,122,183
FRB and FHLB stock | 266,855 | 164,374
Derivative assets | 82,664 | 83,895
Financial liabilities |  |
Non-interest-bearing deposits | 11,658,129 | 11,596,119
Non-time interest-bearing deposits | 29,727,720 | 29,883,378
Time deposits | 8,539,158 | 9,615,862
Total deposits | 49,925,007 | 51,095,359
Federal funds purchased, securities sold under repurchase agreements, and other short-term borrowings | 85,327 | 131,728
Long-term debt | 3,909,478 | 1,733,109
Mutual funds held in rabbi trusts | 54,318 | 48,351
Derivative liabilities | 134,644 | 216,325
Fair Value |  |
Financial assets |  |
Total cash, cash equivalents, and restricted cash | 2,852,316 | 2,993,987
Trading securities | 15,475 | 9,713
Investment securities held to maturity | 2,476,289 | 2,524,525
Investment securities available for sale | 7,798,824 | 7,551,018
Loans held for sale | 152,640 | 89,901
Other investments | 16,899 | 14,831
Mutual funds and mutual funds held in rabbi trusts | 69,686 | 63,371
Loans, net | 42,231,633 | 41,014,425
FRB and FHLB stock | 266,855 | 164,374
Derivative assets | 82,664 | 83,895
Financial liabilities |  |
Non-interest-bearing deposits | 11,658,129 | 11,596,119
Non-time interest-bearing deposits | 29,727,720 | 29,883,378
Time deposits | 8,503,962 | 9,587,417
Total deposits | 49,889,811 | 51,066,914
Federal funds purchased, securities sold under repurchase agreements, and other short-term borrowings | 85,327 | 131,728
Long-term debt | 3,923,662 | 1,748,723
Mutual funds held in rabbi trusts | 54,318 | 48,351
Derivative liabilities | $ 134,644 | $ 216,325

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