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Fair Value Measurement (Schedule Of Fair Value Assets And Liabilities Measured On Recurring Basis) (Details) - USD ($) $ in Thousands | Mar. 31, 2024 | Dec. 31, 2023 | Mar. 31, 2023 | Dec. 31, 2022
--- | --- | --- | --- | ---
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Equity and other investment securities | $ 77,203 | $ 76,995 |  |
Investment securities available for sale | 8,616,545 | 8,829,870 |  |
Loans held for sale | 47,201 | 30,715 |  |
Loans Receivable, Fair Value Disclosure | 267,806 | 275,140 |  |
Residential mortgage servicing rights, at fair value | 110,444 | 109,243 | $ 178,800 | $ 185,017
Derivative Asset | 114,763 | 38,085 |  |
Total assets measured at fair value | 9,233,962 | 9,360,048 |  |
Junior subordinated debentures, at fair value | 309,544 | 316,440 |  |
Derivative Liability | 312,489 | 261,091 |  |
Total liabilities measured at fair value | 622,033 | 577,531 |  |
Foreign currency derivatives |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Derivative Asset | 326 | 457 |  |
Derivative Liability | 182 | 355 |  |
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 | 62,497 | 63,298 |  |
Equity securities held in rabbi trusts |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Equity and other investment securities | 14,706 | 13,697 |  |
U.S. Treasury and agencies |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Investment securities available for sale | 1,467,393 | 1,478,392 |  |
Obligations of states and political subdivisions |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Investment securities available for sale | 1,051,929 | 1,072,105 |  |
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 | 6,097,223 | 6,279,373 |  |
Interest rate lock commitments |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Derivative Asset | 16 |  |  |
Derivative Liability |  | 137 |  |
Interest rate futures |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Derivative Asset | 3,745 |  |  |
Derivative Liability | 1,134 |  |  |
Interest rate forward sales commitments |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Derivative Asset | 74 | 9 |  |
Derivative Liability | 188 | 535 |  |
Interest rate swaps |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Derivative Asset | 114,347 | 33,874 |  |
Derivative Liability | 310,985 | 260,064 |  |
Level 1 |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Loans held for sale | 0 | 0 |  |
Loans Receivable, Fair Value Disclosure | 0 | 0 |  |
Residential mortgage servicing rights, at fair value | 0 | 0 |  |
Total assets measured at fair value | 431,609 | 432,200 |  |
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] |  |  |  |
Derivative Asset | 0 | 0 |  |
Derivative Liability | 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 | 44,038 | 44,839 |  |
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 | 14,706 | 13,697 |  |
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 | 372,865 | 373,664 |  |
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] |  |  |  |
Derivative Asset | 0 |  |  |
Derivative Liability |  | 0 |  |
Level 1 | Interest rate futures |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Derivative Asset | 0 |  |  |
Derivative Liability | 0 |  |  |
Level 1 | Interest rate forward sales commitments |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Derivative Asset | 0 | 0 |  |
Derivative Liability | 0 | 0 |  |
Level 1 | Interest rate swaps |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Derivative Asset | 0 | 0 |  |
Derivative Liability | 0 | 0 |  |
Level 2 |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Loans held for sale | 47,201 | 30,715 |  |
Loans Receivable, Fair Value Disclosure | 267,806 | 275,140 |  |
Residential mortgage servicing rights, at fair value | 0 | 0 |  |
Total assets measured at fair value | 8,691,893 | 8,818,605 |  |
Junior subordinated debentures, at fair value | 0 | 0 |  |
Total liabilities measured at fair value | 312,489 | 260,954 |  |
Level 2 | Foreign currency derivatives |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Derivative Asset | 326 | 457 |  |
Derivative Liability | 182 | 355 |  |
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 | 18,459 |  |
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 | 1,094,528 | 1,104,728 |  |
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 | 1,051,929 | 1,072,105 |  |
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 | 6,097,223 | 6,279,373 |  |
Level 2 | Interest rate lock commitments |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Derivative Asset | 0 |  |  |
Derivative Liability |  | 0 |  |
Level 2 | Interest rate futures |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Derivative Asset | 3,745 |  |  |
Derivative Liability | 1,134 |  |  |
Level 2 | Interest rate forward sales commitments |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Derivative Asset | 74 | 9 |  |
Derivative Liability | 188 | 535 |  |
Level 2 | Interest rate swaps |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Derivative Asset | 114,347 | 33,874 |  |
Derivative Liability | 310,985 | 260,064 |  |
Level 3 |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Loans held for sale | 0 | 0 |  |
Loans Receivable, Fair Value Disclosure | 0 | 0 |  |
Residential mortgage servicing rights, at fair value | 110,444 | 109,243 |  |
Total assets measured at fair value | 110,460 | 109,243 |  |
Junior subordinated debentures, at fair value | 309,544 | 316,440 |  |
Total liabilities measured at fair value | 309,544 | 316,577 |  |
Level 3 | Foreign currency derivatives |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Derivative Asset | 0 | 0 |  |
Derivative Liability | 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] |  |  |  |
Derivative Asset | 16 |  |  |
Derivative Liability |  | 137 |  |
Level 3 | Interest rate futures |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Derivative Asset | 0 |  |  |
Derivative Liability | 0 |  |  |
Level 3 | Interest rate forward sales commitments |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Derivative Asset | 0 | 0 |  |
Derivative Liability | 0 | 0 |  |
Level 3 | Interest rate swaps |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Derivative Asset | 0 | 0 |  |
Derivative Liability | $ 0 | $ 0 |  |

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