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Fair Value Accounting - Schedule of Assets and Liabilities Measured at Estimated Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands | Jun. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Assets |  |
Investment securities available for sale | $ 7,798,824 | $ 7,551,018
Mortgage loans held for sale | 45,136 | 33,448
Derivatives Not Designated as Hedging Instruments |  |
Liabilities |  |
Estimated fair value of derivative liabilities | 134,690 | 201,917
Visa derivative | Derivatives Not Designated as Hedging Instruments |  |
Liabilities |  |
Estimated fair value of derivative liabilities | 62 | 64
U.S. Treasury securities |  |
Assets |  |
Investment securities available for sale | 1,240,926 | 1,212,742
Mortgage-backed securities issued by U.S. Government agencies |  |
Assets |  |
Investment securities available for sale | 1,456,888 | 1,462,790
Mortgage-backed securities issued by U.S. Government sponsored enterprises |  |
Assets |  |
Investment securities available for sale | 2,041,389 | 2,034,035
Collateralized mortgage obligations issued by U.S. Government sponsored enterprises |  |
Assets |  |
Investment securities available for sale | 535,669 | 550,201
Commercial mortgage-backed securities issued by U.S. Government agencies or sponsored enterprises |  |
Assets |  |
Investment securities available for sale | 2,485,074 | 2,253,116
Corporate debt securities and other debt securities |  |
Assets |  |
Investment securities available for sale | 9,167 | 8,971
Level 1 |  |
Assets |  |
Trading securities | 4,000 | 0
Investment securities available for sale | 1,240,926 | 1,212,742
Other investments | 0 | 0
Mutual funds and mutual funds held in rabbi trusts | 69,686 | 63,371
Derivative assets | 0 | 0
Liabilities |  |
Mutual funds held in rabbi trusts | 54,318 | 48,351
Derivative liabilities | 0 | 0
Level 2 |  |
Assets |  |
Trading securities | 11,475 | 9,713
Investment securities available for sale | 6,557,898 | 6,338,276
Other investments | 0 | 0
Mutual funds and mutual funds held in rabbi trusts | 0 | 0
Derivative assets | 82,664 | 83,895
Liabilities |  |
Mutual funds held in rabbi trusts | 0 | 0
Derivative liabilities | 134,644 | 216,325
Level 3 |  |
Assets |  |
Trading securities | 0 | 0
Investment securities available for sale | 0 | 0
Other investments | 16,899 | 14,831
Mutual funds and mutual funds held in rabbi trusts | 0 | 0
Derivative assets | 0 | 0
Liabilities |  |
Mutual funds held in rabbi trusts | 0 | 0
Derivative liabilities | 0 | 0
Fair Value, Measurements, Recurring Basis |  |
Assets |  |
Trading securities | 15,475 | 9,713
Investment securities available for sale | 7,798,824 | 7,551,018
Mortgage loans held for sale | 45,136 | 33,448
Other investments | 16,899 | 14,831
Mutual funds and mutual funds held in rabbi trusts | 69,686 | 63,371
Derivative assets | 82,664 | 83,895
Liabilities |  |
Mutual funds held in rabbi trusts | 54,318 | 48,351
Derivative liabilities | 134,644 | 216,325
Fair Value, Measurements, Recurring Basis | U.S. Treasury securities |  |
Assets |  |
Trading securities | 4,000 | 0
Investment securities available for sale | 1,240,926 | 1,212,742
Fair Value, Measurements, Recurring Basis | State and municipal securities |  |
Assets |  |
Trading securities | 59 | 473
Fair Value, Measurements, Recurring Basis | Asset-backed securities |  |
Assets |  |
Trading securities | 11,312 | 9,240
Fair Value, Measurements, Recurring Basis | Other Investments |  |
Assets |  |
Trading securities | 104 | 0
Fair Value, Measurements, Recurring Basis | U.S. Government agency securities |  |
Assets |  |
Investment securities available for sale | 29,711 | 29,163
Fair Value, Measurements, Recurring Basis | Mortgage-backed securities issued by U.S. Government agencies |  |
Assets |  |
Investment securities available for sale | 1,456,888 | 1,462,790
Fair Value, Measurements, Recurring Basis | Mortgage-backed securities issued by U.S. Government sponsored enterprises |  |
Assets |  |
Investment securities available for sale | 2,041,389 | 2,034,035
Fair Value, Measurements, Recurring Basis | Collateralized mortgage obligations issued by U.S. Government sponsored enterprises |  |
Assets |  |
Investment securities available for sale | 535,669 | 550,201
Fair Value, Measurements, Recurring Basis | Commercial mortgage-backed securities issued by U.S. Government agencies or sponsored enterprises |  |
Assets |  |
Investment securities available for sale | 2,485,074 | 2,253,116
Fair Value, Measurements, Recurring Basis | Corporate debt securities and other debt securities |  |
Assets |  |
Investment securities available for sale | 9,167 | 8,971
Fair Value, Measurements, Recurring Basis | Level 1 |  |
Assets |  |
Trading securities | 4,000 | 0
Investment securities available for sale | 1,240,926 | 1,212,742
Mortgage loans held for sale | 0 | 0
Other investments | 0 | 0
Mutual funds and mutual funds held in rabbi trusts | 69,686 | 63,371
Derivative assets | 0 | 0
Liabilities |  |
Mutual funds held in rabbi trusts | 54,318 | 48,351
Derivative liabilities | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 1 | U.S. Treasury securities |  |
Assets |  |
Trading securities | 4,000 | 0
Investment securities available for sale | 1,240,926 | 1,212,742
Fair Value, Measurements, Recurring Basis | Level 1 | State and municipal securities |  |
Assets |  |
Trading securities | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 1 | Asset-backed securities |  |
Assets |  |
Trading securities | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 1 | Other Investments |  |
Assets |  |
Trading securities | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 1 | U.S. Government agency securities |  |
Assets |  |
Investment securities available for sale | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 1 | Mortgage-backed securities issued by U.S. Government agencies |  |
Assets |  |
Investment securities available for sale | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 1 | Mortgage-backed securities issued by U.S. Government sponsored enterprises |  |
Assets |  |
Investment securities available for sale | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 1 | Collateralized mortgage obligations issued by U.S. Government sponsored enterprises |  |
Assets |  |
Investment securities available for sale | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 1 | Commercial mortgage-backed securities issued by U.S. Government agencies or sponsored enterprises |  |
Assets |  |
Investment securities available for sale | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 1 | Corporate debt securities and other debt securities |  |
Assets |  |
Investment securities available for sale | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 2 |  |
Assets |  |
Trading securities | 11,475 | 9,713
Investment securities available for sale | 6,557,898 | 6,338,276
Mortgage loans held for sale | 45,136 | 33,448
Other investments | 0 | 0
Mutual funds and mutual funds held in rabbi trusts | 0 | 0
Derivative assets | 82,664 | 83,895
Liabilities |  |
Mutual funds held in rabbi trusts | 0 | 0
Derivative liabilities | 134,644 | 216,325
Fair Value, Measurements, Recurring Basis | Level 2 | U.S. Treasury securities |  |
Assets |  |
Trading securities | 0 | 0
Investment securities available for sale | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 2 | State and municipal securities |  |
Assets |  |
Trading securities | 59 | 473
Fair Value, Measurements, Recurring Basis | Level 2 | Asset-backed securities |  |
Assets |  |
Trading securities | 11,312 | 9,240
Fair Value, Measurements, Recurring Basis | Level 2 | Other Investments |  |
Assets |  |
Trading securities | 104 | 0
Fair Value, Measurements, Recurring Basis | Level 2 | U.S. Government agency securities |  |
Assets |  |
Investment securities available for sale | 29,711 | 29,163
Fair Value, Measurements, Recurring Basis | Level 2 | Mortgage-backed securities issued by U.S. Government agencies |  |
Assets |  |
Investment securities available for sale | 1,456,888 | 1,462,790
Fair Value, Measurements, Recurring Basis | Level 2 | Mortgage-backed securities issued by U.S. Government sponsored enterprises |  |
Assets |  |
Investment securities available for sale | 2,041,389 | 2,034,035
Fair Value, Measurements, Recurring Basis | Level 2 | Collateralized mortgage obligations issued by U.S. Government sponsored enterprises |  |
Assets |  |
Investment securities available for sale | 535,669 | 550,201
Fair Value, Measurements, Recurring Basis | Level 2 | Commercial mortgage-backed securities issued by U.S. Government agencies or sponsored enterprises |  |
Assets |  |
Investment securities available for sale | 2,485,074 | 2,253,116
Fair Value, Measurements, Recurring Basis | Level 2 | Corporate debt securities and other debt securities |  |
Assets |  |
Investment securities available for sale | 9,167 | 8,971
Fair Value, Measurements, Recurring Basis | Level 3 |  |
Assets |  |
Trading securities | 0 | 0
Investment securities available for sale | 0 | 0
Mortgage loans held for sale | 0 | 0
Other investments | 16,899 | 14,831
Mutual funds and mutual funds held in rabbi trusts | 0 | 0
Derivative assets | 0 | 0
Liabilities |  |
Mutual funds held in rabbi trusts | 0 | 0
Derivative liabilities | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 3 | U.S. Treasury securities |  |
Assets |  |
Trading securities | 0 | 0
Investment securities available for sale | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 3 | State and municipal securities |  |
Assets |  |
Trading securities | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 3 | Asset-backed securities |  |
Assets |  |
Trading securities | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 3 | Other Investments |  |
Assets |  |
Trading securities | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 3 | U.S. Government agency securities |  |
Assets |  |
Investment securities available for sale | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 3 | Mortgage-backed securities issued by U.S. Government agencies |  |
Assets |  |
Investment securities available for sale | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 3 | Mortgage-backed securities issued by U.S. Government sponsored enterprises |  |
Assets |  |
Investment securities available for sale | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 3 | Collateralized mortgage obligations issued by U.S. Government sponsored enterprises |  |
Assets |  |
Investment securities available for sale | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 3 | Commercial mortgage-backed securities issued by U.S. Government agencies or sponsored enterprises |  |
Assets |  |
Investment securities available for sale | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 3 | Corporate debt securities and other debt securities |  |
Assets |  |
Investment securities available for sale | $ 0 | $ 0

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