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Fair Value Accounting - Financial Instruments Measured At Fair Value On A Recurring Basis (Details) - USD ($) $ in Thousands | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
--- | --- | --- | ---
Assets |  |  |
Total investment securities available for sale | $ 9,788,662 | $ 9,678,103 |
Mortgage loans held for sale | 47,338 | 51,136 | $ 108,198
Mutual funds and mutual funds held in rabbi trusts | 53,742 | 42,659 |
Derivative assets | 94,903 | 89,815 |
Not Designated As Hedging Instruments |  |  |
Liabilities |  |  |
Fair value of derivative liabilities | 239,821 | 326,301 |
Visa Derivative Liability | Not Designated As Hedging Instruments |  |  |
Liabilities |  |  |
Fair value of derivative liabilities | 589 | 3,453 |
Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises |  |  |
Assets |  |  |
Total investment securities available for sale | 587,595 | 655,127 |
U.S. Treasury securities |  |  |
Assets |  |  |
Total investment securities available for sale | 597,629 | 471,813 |
Mortgage-backed securities issued by U.S. Government agencies |  |  |
Assets |  |  |
Total investment securities available for sale | 925,664 | 792,749 |
Mortgage-backed securities issued by U.S. Government sponsored enterprises |  |  |
Assets |  |  |
Total investment securities available for sale | 6,430,379 | 6,895,070 |
Commercial mortgage-backed securities issued by U.S. Government agencies or sponsored enterprises |  |  |
Assets |  |  |
Total investment securities available for sale | 1,209,783 | 805,945 |
Corporate debt securities and other debt securities |  |  |
Assets |  |  |
Total investment securities available for sale | 8,672 | 8,601 |
Fair Value, Measurements, Recurring |  |  |
Assets |  |  |
Total trading securities | 12,898 | 8,295 |
Total investment securities available for sale | 9,788,662 | 9,678,103 |
Mortgage loans held for sale | 47,338 | 51,136 |
Other investments | 12,560 | 11,172 |
Mutual funds and mutual funds held in rabbi trusts | 53,742 | 42,659 |
Derivative assets | 94,903 | 89,815 |
Liabilities |  |  |
Securities sold short | 3,496 | 3,370 |
Mutual fund held in rabbi trusts | 38,735 | 27,944 |
Derivative liabilities | 259,650 | 339,227 |
Fair Value, Measurements, Recurring | Level 1 |  |  |
Assets |  |  |
Total trading securities | 0 | 0 |
Total investment securities available for sale | 597,629 | 471,813 |
Mortgage loans held for sale | 0 | 0 |
Other investments | 0 | 0 |
Mutual funds and mutual funds held in rabbi trusts | 53,742 | 42,659 |
Derivative assets | 0 | 0 |
Liabilities |  |  |
Securities sold short | 3,496 | 3,370 |
Mutual fund held in rabbi trusts | 38,735 | 27,944 |
Derivative liabilities | 0 | 0 |
Fair Value, Measurements, Recurring | Level 2 |  |  |
Assets |  |  |
Total trading securities | 12,898 | 8,295 |
Total investment securities available for sale | 9,191,033 | 9,206,290 |
Mortgage loans held for sale | 47,338 | 51,136 |
Other investments | 0 | 0 |
Mutual funds and mutual funds held in rabbi trusts | 0 | 0 |
Derivative assets | 94,903 | 89,815 |
Liabilities |  |  |
Securities sold short | 0 | 0 |
Mutual fund held in rabbi trusts | 0 | 0 |
Derivative liabilities | 259,650 | 339,227 |
Fair Value, Measurements, Recurring | Level 3 |  |  |
Assets |  |  |
Total trading securities | 0 | 0 |
Total investment securities available for sale | 0 | 0 |
Mortgage loans held for sale | 0 | 0 |
Other investments | 12,560 | 11,172 |
Mutual funds and mutual funds held in rabbi trusts | 0 | 0 |
Derivative assets | 0 | 0 |
Liabilities |  |  |
Securities sold short | 0 | 0 |
Mutual fund held in rabbi trusts | 0 | 0 |
Derivative liabilities | 0 | 0 |
Fair Value, Measurements, Recurring | Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises |  |  |
Assets |  |  |
Total trading securities | 2,910 | 2,991 |
Total investment securities available for sale | 587,595 | 655,127 |
Fair Value, Measurements, Recurring | Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises | Level 1 |  |  |
Assets |  |  |
Total trading securities | 0 | 0 |
Total investment securities available for sale | 0 | 0 |
Fair Value, Measurements, Recurring | Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises | Level 2 |  |  |
Assets |  |  |
Total trading securities | 2,910 | 2,991 |
Total investment securities available for sale | 587,595 | 655,127 |
Fair Value, Measurements, Recurring | Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises | Level 3 |  |  |
Assets |  |  |
Total trading securities | 0 | 0 |
Total investment securities available for sale | 0 | 0 |
Fair Value, Measurements, Recurring | Other mortgage-backed securities |  |  |
Assets |  |  |
Total trading securities | 2,149 | 3,185 |
Fair Value, Measurements, Recurring | Other mortgage-backed securities | Level 1 |  |  |
Assets |  |  |
Total trading securities | 0 | 0 |
Fair Value, Measurements, Recurring | Other mortgage-backed securities | Level 2 |  |  |
Assets |  |  |
Total trading securities | 2,149 | 3,185 |
Fair Value, Measurements, Recurring | Other mortgage-backed securities | Level 3 |  |  |
Assets |  |  |
Total trading securities | 0 | 0 |
Fair Value, Measurements, Recurring | State and municipal securities |  |  |
Assets |  |  |
Total trading securities | 0 | 48 |
Fair Value, Measurements, Recurring | State and municipal securities | Level 1 |  |  |
Assets |  |  |
Total trading securities | 0 | 0 |
Fair Value, Measurements, Recurring | State and municipal securities | Level 2 |  |  |
Assets |  |  |
Total trading securities | 0 | 48 |
Fair Value, Measurements, Recurring | State and municipal securities | Level 3 |  |  |
Assets |  |  |
Total trading securities | 0 | 0 |
Fair Value, Measurements, Recurring | Asset-backed securities |  |  |
Assets |  |  |
Total trading securities | 7,839 | 2,071 |
Fair Value, Measurements, Recurring | Asset-backed securities | Level 1 |  |  |
Assets |  |  |
Total trading securities | 0 | 0 |
Fair Value, Measurements, Recurring | Asset-backed securities | Level 2 |  |  |
Assets |  |  |
Total trading securities | 7,839 | 2,071 |
Fair Value, Measurements, Recurring | Asset-backed securities | Level 3 |  |  |
Assets |  |  |
Total trading securities | 0 | 0 |
Fair Value, Measurements, Recurring | U.S. Treasury securities |  |  |
Assets |  |  |
Total investment securities available for sale | 597,629 | 471,813 |
Fair Value, Measurements, Recurring | U.S. Treasury securities | Level 1 |  |  |
Assets |  |  |
Total investment securities available for sale | 597,629 | 471,813 |
Fair Value, Measurements, Recurring | U.S. Treasury securities | Level 2 |  |  |
Assets |  |  |
Total investment securities available for sale | 0 | 0 |
Fair Value, Measurements, Recurring | U.S. Treasury securities | Level 3 |  |  |
Assets |  |  |
Total investment securities available for sale | 0 | 0 |
Fair Value, Measurements, Recurring | U.S. Government agency securities |  |  |
Assets |  |  |
Total investment securities available for sale | 28,940 | 48,798 |
Fair Value, Measurements, Recurring | U.S. Government agency securities | Level 1 |  |  |
Assets |  |  |
Total investment securities available for sale | 0 | 0 |
Fair Value, Measurements, Recurring | U.S. Government agency securities | Level 2 |  |  |
Assets |  |  |
Total investment securities available for sale | 28,940 | 48,798 |
Fair Value, Measurements, Recurring | U.S. Government agency securities | Level 3 |  |  |
Assets |  |  |
Total investment securities available for sale | 0 | 0 |
Fair Value, Measurements, Recurring | Mortgage-backed securities issued by U.S. Government agencies |  |  |
Assets |  |  |
Total investment securities available for sale | 925,664 | 792,749 |
Fair Value, Measurements, Recurring | Mortgage-backed securities issued by U.S. Government agencies | Level 1 |  |  |
Assets |  |  |
Total investment securities available for sale | 0 | 0 |
Fair Value, Measurements, Recurring | Mortgage-backed securities issued by U.S. Government agencies | Level 2 |  |  |
Assets |  |  |
Total investment securities available for sale | 925,664 | 792,749 |
Fair Value, Measurements, Recurring | Mortgage-backed securities issued by U.S. Government agencies | Level 3 |  |  |
Assets |  |  |
Total investment securities available for sale | 0 | 0 |
Fair Value, Measurements, Recurring | Mortgage-backed securities issued by U.S. Government sponsored enterprises |  |  |
Assets |  |  |
Total investment securities available for sale | 6,430,379 | 6,895,070 |
Fair Value, Measurements, Recurring | Mortgage-backed securities issued by U.S. Government sponsored enterprises | Level 1 |  |  |
Assets |  |  |
Total investment securities available for sale | 0 | 0 |
Fair Value, Measurements, Recurring | Mortgage-backed securities issued by U.S. Government sponsored enterprises | Level 2 |  |  |
Assets |  |  |
Total investment securities available for sale | 6,430,379 | 6,895,070 |
Fair Value, Measurements, Recurring | Mortgage-backed securities issued by U.S. Government sponsored enterprises | Level 3 |  |  |
Assets |  |  |
Total investment securities available for sale | 0 | 0 |
Fair Value, Measurements, Recurring | Commercial mortgage-backed securities issued by U.S. Government agencies or sponsored enterprises |  |  |
Assets |  |  |
Total investment securities available for sale | 1,209,783 | 805,945 |
Fair Value, Measurements, Recurring | Commercial mortgage-backed securities issued by U.S. Government agencies or sponsored enterprises | Level 1 |  |  |
Assets |  |  |
Total investment securities available for sale | 0 | 0 |
Fair Value, Measurements, Recurring | Commercial mortgage-backed securities issued by U.S. Government agencies or sponsored enterprises | Level 2 |  |  |
Assets |  |  |
Total investment securities available for sale | 1,209,783 | 805,945 |
Fair Value, Measurements, Recurring | Commercial mortgage-backed securities issued by U.S. Government agencies or sponsored enterprises | Level 3 |  |  |
Assets |  |  |
Total investment securities available for sale | 0 | 0 |
Fair Value, Measurements, Recurring | Corporate debt securities and other debt securities |  |  |
Assets |  |  |
Total investment securities available for sale | 8,672 | 8,601 |
Fair Value, Measurements, Recurring | Corporate debt securities and other debt securities | Level 1 |  |  |
Assets |  |  |
Total investment securities available for sale | 0 | 0 |
Fair Value, Measurements, Recurring | Corporate debt securities and other debt securities | Level 2 |  |  |
Assets |  |  |
Total investment securities available for sale | 8,672 | 8,601 |
Fair Value, Measurements, Recurring | Corporate debt securities and other debt securities | Level 3 |  |  |
Assets |  |  |
Total investment securities available for sale | $ 0 | $ 0 |

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- Definition Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. 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