Fair Value Measurement (Schedule Of Carrying Value And Fair Value Of Financial Instruments Not Recorded At Fair Value) (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023	Dec. 31, 2022
Financial assets:
Equity and other investment securities	$ 77,203	$ 76,995
Investment securities available for sale	8,616,545	8,829,870
Investment securities held to maturity	2,247	2,300
Loans held for sale	47,201	30,715
Loans and leases, net	37,228,069	37,001,080
Restricted equity securities	116,274	179,274
Residential mortgage servicing rights	110,444	109,243	$ 178,800	$ 185,017
Bank-owned life insurance	682,293	680,948
Derivatives	114,763	38,085
Financial liabilities:
Securities sold under agreements to repurchase	213,573	252,119
Borrowings	3,900,000	3,950,000
Junior subordinated debentures, at fair value	309,544	316,440
Junior and other subordinated debentures, at amortized cost	107,838	107,895
Derivatives	312,489	261,091
Carrying Value
Financial assets:
Cash and cash equivalents	2,201,117	2,162,534
Equity and other investment securities	77,203	76,995
Investment securities available for sale	8,616,545	8,829,870
Investment securities held to maturity	2,247	2,300
Loans held for sale	47,201	30,715
Loans and leases, net	37,228,069	37,001,080
Restricted equity securities	116,274	179,274
Residential mortgage servicing rights	110,444	109,243
Bank-owned life insurance	682,293	680,948
Derivatives	114,763	38,085
Financial liabilities:
Demand, money market, and savings deposits	35,366,323	35,379,451
Time Deposits	6,339,837	6,227,569
Securities sold under agreements to repurchase	213,573	252,119
Borrowings	3,900,000	3,950,000
Junior subordinated debentures, at fair value	309,544	316,440
Junior and other subordinated debentures, at amortized cost	107,838	107,895
Derivatives	312,489	261,091
Fair Value
Financial assets:
Cash and cash equivalents	2,201,117	2,162,534
Equity and other investment securities	77,203	76,995
Investment securities available for sale	8,616,545	8,829,870
Investment securities held to maturity	2,939	3,025
Loans held for sale	47,201	30,715
Loans and leases, net	35,740,658	35,810,989
Restricted equity securities	116,274	179,274
Residential mortgage servicing rights	110,444	109,243
Bank-owned life insurance	682,293	680,948
Derivatives	114,763	38,085
Financial liabilities:
Demand, money market, and savings deposits	35,366,323	35,379,451
Time Deposits	6,314,381	6,201,519
Securities sold under agreements to repurchase	213,573	252,119
Borrowings	3,893,589	3,950,037
Junior subordinated debentures, at fair value	309,544	316,440
Junior and other subordinated debentures, at amortized cost	98,867	97,695
Derivatives	$ 312,489	$ 261,091