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Fair Value Measurement (Schedule Of Fair Value Assets And Liabilities Measured On Recurring Basis) (Details) - USD ($) $ in Thousands | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
--- | --- | --- | --- | ---
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Equity and other investment securities | $ 76,995 | $ 72,959 |  |
Investment securities available for sale | 8,829,870 | 3,196,166 |  |
Loans held for sale, at fair value | 30,715 | 71,647 |  |
Loans and leases, at fair value | 275,140 | 285,581 |  |
Residential mortgage servicing rights, at fair value | 109,243 | 185,017 | $ 123,615 | $ 92,907
Derivatives, assets | 38,085 | 15,444 |  |
Total assets measured at fair value | 9,360,048 | 3,826,814 |  |
Junior subordinated debentures, at fair value | 316,440 | 323,639 |  |
Derivatives, liabilities | 261,091 | 271,205 |  |
Total liabilities measured at fair value | 577,531 | 594,844 |  |
Foreign currency derivatives |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Derivatives, assets | 457 | 225 |  |
Derivatives, liabilities | 355 | 185 |  |
Investments in mutual funds and other securities |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Equity and other investment securities | 63,298 | 61,593 |  |
Equity securities held in rabbi trusts |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Equity and other investment securities | 13,697 | 11,366 |  |
U.S. Treasury and agencies |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Investment securities available for sale | 1,478,392 | 936,174 |  |
Obligations of states and political subdivisions |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Investment securities available for sale | 1,072,105 | 269,800 |  |
Mortgage-backed securities and collateralized mortgage obligations |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Investment securities available for sale | 6,279,373 | 1,990,192 |  |
Interest rate lock commitments |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Derivatives, assets |  | 50 |  |
Derivatives, liabilities | 137 | 18 |  |
Interest Rate Futures Contracts |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Derivatives, liabilities | 3,745 | 392 |  |
Interest rate forward sales commitments |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Derivatives, assets | 9 | 512 |  |
Derivatives, liabilities | 535 | 601 |  |
Interest rate swaps |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Derivatives, assets | 33,874 | 14,657 |  |
Derivatives, liabilities | 260,064 | 270,009 |  |
Level 1 |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Loans held for sale, at fair value | 0 | 0 |  |
Loans and leases, at fair value | 0 | 0 |  |
Residential mortgage servicing rights, at fair value | 0 | 0 |  |
Total assets measured at fair value | 432,200 | 281,475 |  |
Junior subordinated debentures, at fair value | 0 | 0 |  |
Total liabilities measured at fair value | 0 | 0 |  |
Level 1 | Foreign currency derivatives |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Derivatives, assets | 0 | 0 |  |
Derivatives, liabilities | 0 | 0 |  |
Level 1 | Investments in mutual funds and other securities |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Equity and other investment securities | 44,839 | 44,256 |  |
Level 1 | Equity securities held in rabbi trusts |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Equity and other investment securities | 13,697 | 11,366 |  |
Level 1 | U.S. Treasury and agencies |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Investment securities available for sale | 373,664 | 225,853 |  |
Level 1 | Obligations of states and political subdivisions |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Investment securities available for sale | 0 | 0 |  |
Level 1 | Mortgage-backed securities and collateralized mortgage obligations |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Investment securities available for sale | 0 | 0 |  |
Level 1 | Interest rate lock commitments |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Derivatives, assets |  | 0 |  |
Derivatives, liabilities | 0 | 0 |  |
Level 1 | Interest Rate Futures Contracts |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Derivatives, liabilities | 0 | 0 |  |
Level 1 | Interest rate forward sales commitments |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Derivatives, assets | 0 | 0 |  |
Derivatives, liabilities | 0 | 0 |  |
Level 1 | Interest rate swaps |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Derivatives, assets | 0 | 0 |  |
Derivatives, liabilities | 0 | 0 |  |
Level 2 |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Loans held for sale, at fair value | 30,715 | 71,647 |  |
Loans and leases, at fair value | 275,140 | 285,581 |  |
Residential mortgage servicing rights, at fair value | 0 | 0 |  |
Total assets measured at fair value | 8,818,605 | 3,360,272 |  |
Junior subordinated debentures, at fair value | 0 | 0 |  |
Total liabilities measured at fair value | 260,954 | 271,187 |  |
Level 2 | Foreign currency derivatives |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Derivatives, assets | 457 | 225 |  |
Derivatives, liabilities | 355 | 185 |  |
Level 2 | Investments in mutual funds and other securities |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Equity and other investment securities | 18,459 | 17,337 |  |
Level 2 | Equity securities held in rabbi trusts |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Equity and other investment securities | 0 | 0 |  |
Level 2 | U.S. Treasury and agencies |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Investment securities available for sale | 1,104,728 | 710,321 |  |
Level 2 | Obligations of states and political subdivisions |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Investment securities available for sale | 1,072,105 | 269,800 |  |
Level 2 | Mortgage-backed securities and collateralized mortgage obligations |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Investment securities available for sale | 6,279,373 | 1,990,192 |  |
Level 2 | Interest rate lock commitments |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Derivatives, assets |  | 0 |  |
Derivatives, liabilities | 0 | 0 |  |
Level 2 | Interest Rate Futures Contracts |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Derivatives, liabilities | 3,745 | 392 |  |
Level 2 | Interest rate forward sales commitments |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Derivatives, assets | 9 | 512 |  |
Derivatives, liabilities | 535 | 601 |  |
Level 2 | Interest rate swaps |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Derivatives, assets | 33,874 | 14,657 |  |
Derivatives, liabilities | 260,064 | 270,009 |  |
Level 3 |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Loans held for sale, at fair value | 0 | 0 |  |
Loans and leases, at fair value | 0 | 0 |  |
Residential mortgage servicing rights, at fair value | 109,243 | 185,017 |  |
Total assets measured at fair value | 109,243 | 185,067 |  |
Junior subordinated debentures, at fair value | 316,440 | 323,639 |  |
Total liabilities measured at fair value | 316,577 | 323,657 |  |
Level 3 | Foreign currency derivatives |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Derivatives, assets | 0 | 0 |  |
Derivatives, liabilities | 0 | 0 |  |
Level 3 | Investments in mutual funds and other securities |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Equity and other investment securities | 0 | 0 |  |
Level 3 | Equity securities held in rabbi trusts |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Equity and other investment securities | 0 | 0 |  |
Level 3 | U.S. Treasury and agencies |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Investment securities available for sale | 0 | 0 |  |
Level 3 | Obligations of states and political subdivisions |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Investment securities available for sale | 0 | 0 |  |
Level 3 | Mortgage-backed securities and collateralized mortgage obligations |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Investment securities available for sale | 0 | 0 |  |
Level 3 | Interest rate lock commitments |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Derivatives, assets |  | 50 |  |
Derivatives, liabilities | 137 | 18 |  |
Level 3 | Interest Rate Futures Contracts |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Derivatives, liabilities | 0 | 0 |  |
Level 3 | Interest rate forward sales commitments |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Derivatives, assets | 0 | 0 |  |
Derivatives, liabilities | 0 | 0 |  |
Level 3 | Interest rate swaps |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Derivatives, assets | 0 | 0 |  |
Derivatives, liabilities | $ 0 | $ 0 |  |

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