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Fair Value Accounting - Financial Instruments Measured At Fair Value On A Recurring Basis (Details) - USD ($) $ in Thousands | Jun. 30, 2024 | Dec. 31, 2023
--- | --- | ---
Assets |  |
Investment securities available for sale | $ 7,043,681 | $ 9,788,662
Mortgage loans held for sale | 41,823 | 47,338
Collateralized mortgage obligations issued by U.S. Government sponsored enterprises |  |
Assets |  |
Investment securities available for sale | 547,997 | 587,595
U.S. Treasury securities |  |
Assets |  |
Investment securities available for sale | 1,174,295 | 597,629
Mortgage-backed securities issued by U.S. Government agencies |  |
Assets |  |
Investment securities available for sale | 1,400,492 | 925,664
Mortgage-backed securities issued by U.S. Government sponsored enterprises |  |
Assets |  |
Investment securities available for sale | 2,016,045 | 6,430,379
Commercial mortgage-backed securities issued by U.S. Government agencies or sponsored enterprises |  |
Assets |  |
Investment securities available for sale | 1,867,126 | 1,209,783
Corporate debt securities and other debt securities |  |
Assets |  |
Investment securities available for sale | 8,883 | 8,672
Level 1 |  |
Assets |  |
Trading securities | 0 | 0
Investment securities available for sale | 1,174,295 | 597,629
Other investments | 0 | 0
Mutual funds and mutual funds held in rabbi trusts | 60,356 | 53,742
Derivative assets | 0 | 0
Liabilities |  |
Securities sold short | 2,536 | 3,496
Mutual funds held in rabbi trusts | 45,479 | 38,735
Derivative liabilities | 0 | 0
Level 2 |  |
Assets |  |
Trading securities | 13,052 | 12,898
Investment securities available for sale | 5,869,386 | 9,191,033
Other investments | 0 | 0
Mutual funds and mutual funds held in rabbi trusts | 0 | 0
Derivative assets | 97,078 | 94,903
Liabilities |  |
Securities sold short | 0 | 0
Mutual funds held in rabbi trusts | 0 | 0
Derivative liabilities | 280,045 | 259,650
Level 3 |  |
Assets |  |
Trading securities | 0 | 0
Investment securities available for sale | 0 | 0
Other investments | 14,423 | 12,560
Mutual funds and mutual funds held in rabbi trusts | 0 | 0
Derivative assets | 0 | 0
Liabilities |  |
Securities sold short | 0 | 0
Mutual funds held in rabbi trusts | 0 | 0
Derivative liabilities | 0 | 0
Fair Value, Measurements, Recurring Basis |  |
Assets |  |
Trading securities | 13,052 | 12,898
Investment securities available for sale | 7,043,681 | 9,788,662
Mortgage loans held for sale | 41,823 | 47,338
Other investments | 14,423 | 12,560
Mutual funds and mutual funds held in rabbi trusts | 60,356 | 53,742
Derivative assets | 97,078 | 94,903
Liabilities |  |
Securities sold short | 2,536 | 3,496
Mutual funds held in rabbi trusts | 45,479 | 38,735
Derivative liabilities | 280,045 | 259,650
Fair Value, Measurements, Recurring Basis | Collateralized mortgage obligations issued by U.S. Government sponsored enterprises |  |
Assets |  |
Trading securities | 2,956 | 2,910
Investment securities available for sale | 547,997 | 587,595
Fair Value, Measurements, Recurring Basis | Other mortgage-backed securities |  |
Assets |  |
Trading securities | 0 | 2,149
Fair Value, Measurements, Recurring Basis | Asset-backed securities |  |
Assets |  |
Trading securities | 10,096 | 7,839
Fair Value, Measurements, Recurring Basis | U.S. Treasury securities |  |
Assets |  |
Investment securities available for sale | 1,174,295 | 597,629
Fair Value, Measurements, Recurring Basis | U.S. Government agency securities |  |
Assets |  |
Investment securities available for sale | 28,843 | 28,940
Fair Value, Measurements, Recurring Basis | Mortgage-backed securities issued by U.S. Government agencies |  |
Assets |  |
Investment securities available for sale | 1,400,492 | 925,664
Fair Value, Measurements, Recurring Basis | Mortgage-backed securities issued by U.S. Government sponsored enterprises |  |
Assets |  |
Investment securities available for sale | 2,016,045 | 6,430,379
Fair Value, Measurements, Recurring Basis | Commercial mortgage-backed securities issued by U.S. Government agencies or sponsored enterprises |  |
Assets |  |
Investment securities available for sale | 1,867,126 | 1,209,783
Fair Value, Measurements, Recurring Basis | Corporate debt securities and other debt securities |  |
Assets |  |
Investment securities available for sale | 8,883 | 8,672
Fair Value, Measurements, Recurring Basis | Level 1 |  |
Assets |  |
Trading securities | 0 | 0
Investment securities available for sale | 1,174,295 | 597,629
Mortgage loans held for sale | 0 | 0
Other investments | 0 | 0
Mutual funds and mutual funds held in rabbi trusts | 60,356 | 53,742
Derivative assets | 0 | 0
Liabilities |  |
Securities sold short | 2,536 | 3,496
Mutual funds held in rabbi trusts | 45,479 | 38,735
Derivative liabilities | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 1 | Collateralized mortgage obligations issued by U.S. Government sponsored enterprises |  |
Assets |  |
Trading securities | 0 | 0
Investment securities available for sale | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 1 | Other mortgage-backed 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 | U.S. Treasury securities |  |
Assets |  |
Investment securities available for sale | 1,174,295 | 597,629
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 | 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 | 13,052 | 12,898
Investment securities available for sale | 5,869,386 | 9,191,033
Mortgage loans held for sale | 41,823 | 47,338
Other investments | 0 | 0
Mutual funds and mutual funds held in rabbi trusts | 0 | 0
Derivative assets | 97,078 | 94,903
Liabilities |  |
Securities sold short | 0 | 0
Mutual funds held in rabbi trusts | 0 | 0
Derivative liabilities | 280,045 | 259,650
Fair Value, Measurements, Recurring Basis | Level 2 | Collateralized mortgage obligations issued by U.S. Government sponsored enterprises |  |
Assets |  |
Trading securities | 2,956 | 2,910
Investment securities available for sale | 547,997 | 587,595
Fair Value, Measurements, Recurring Basis | Level 2 | Other mortgage-backed securities |  |
Assets |  |
Trading securities | 0 | 2,149
Fair Value, Measurements, Recurring Basis | Level 2 | Asset-backed securities |  |
Assets |  |
Trading securities | 10,096 | 7,839
Fair Value, Measurements, Recurring Basis | Level 2 | U.S. Treasury securities |  |
Assets |  |
Investment securities available for sale | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 2 | U.S. Government agency securities |  |
Assets |  |
Investment securities available for sale | 28,843 | 28,940
Fair Value, Measurements, Recurring Basis | Level 2 | Mortgage-backed securities issued by U.S. Government agencies |  |
Assets |  |
Investment securities available for sale | 1,400,492 | 925,664
Fair Value, Measurements, Recurring Basis | Level 2 | Mortgage-backed securities issued by U.S. Government sponsored enterprises |  |
Assets |  |
Investment securities available for sale | 2,016,045 | 6,430,379
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 | 1,867,126 | 1,209,783
Fair Value, Measurements, Recurring Basis | Level 2 | Corporate debt securities and other debt securities |  |
Assets |  |
Investment securities available for sale | 8,883 | 8,672
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 | 14,423 | 12,560
Mutual funds and mutual funds held in rabbi trusts | 0 | 0
Derivative assets | 0 | 0
Liabilities |  |
Securities sold short | 0 | 0
Mutual funds held in rabbi trusts | 0 | 0
Derivative liabilities | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 3 | Collateralized mortgage obligations issued by U.S. Government sponsored enterprises |  |
Assets |  |
Trading securities | 0 | 0
Investment securities available for sale | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 3 | Other mortgage-backed 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 | U.S. Treasury securities |  |
Assets |  |
Investment securities available for sale | 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 | 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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- 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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