Fair Value Measurement (Schedule Of Carrying Value And Fair Value Of Financial Instruments Not Recorded At Fair Value) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Financial assets:
Equity and other investment securities	$ 83,077	$ 80,165
Investment securities available for sale	2,932,558	2,814,682
Investment securities held to maturity	3,034	3,260
Loans held for sale, at fair value		513,431
Loans and leases, net	21,450,966	21,038,055
Restricted equity securities	41,666	46,463
Residential mortgage servicing rights	92,907	115,010	$ 169,025	$ 153,151
Bank owned life insurance	323,470	320,611
Derivatives	342,510	150,574
Financial liabilities:
Deposits	24,622,201	22,481,504	$ 21,137,486
Securities sold under agreements to repurchase	375,384	311,308
Borrowings	771,482	906,635
Junior subordinated debentures, at fair value	255,217	274,812
Junior subordinated debentures, at amortized cost	88,268	88,496
Derivatives	8,782	8,808
Carrying Value
Financial assets:
Cash and cash equivalents	2,573,181	1,362,756
Equity and other investment securities	83,077	80,165
Investment securities available for sale	2,932,558	2,814,682
Investment securities held to maturity	3,034	3,260
Loans held for sale, at fair value	766,225	513,431
Loans and leases, net	21,450,966	21,038,055
Restricted equity securities	41,666	46,463
Residential mortgage servicing rights	92,907	115,010
Bank owned life insurance	323,470	320,611
Derivatives	342,510	150,574
Financial liabilities:
Deposits	24,622,201	22,481,504
Securities sold under agreements to repurchase	375,384	311,308
Borrowings	771,482	906,635
Junior subordinated debentures, at fair value	255,217	274,812
Junior subordinated debentures, at amortized cost	88,268	88,496
Derivatives	8,782	8,808
Estimated Fair Value
Financial assets:
Cash and cash equivalents	2,573,181	1,362,756
Equity and other investment securities	83,077	80,165
Investment securities available for sale	2,932,558	2,814,682
Investment securities held to maturity	3,883	4,263
Loans held for sale, at fair value	766,225	513,431
Loans and leases, net	21,904,189	21,274,319
Restricted equity securities	41,666	46,463
Residential mortgage servicing rights	92,907	115,010
Bank owned life insurance	323,470	320,611
Derivatives	342,510	150,574
Financial liabilities:
Deposits	24,641,876	22,503,916
Securities sold under agreements to repurchase	375,384	311,308
Borrowings	774,586	906,160
Junior subordinated debentures, at fair value	255,217	274,812
Junior subordinated debentures, at amortized cost	67,425	70,909
Derivatives	$ 8,782	$ 8,808

Equity and Other securities in investment securities portfolio

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The carrying value as of the balance sheet date of junior subordinated debentures, at amortized cost.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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The carrying amount of a life insurance policy on an officer, executive or employee for which the reporting entity (a bank) is entitled to proceeds from the policy upon death of the insured or surrender of the insurance policy.

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

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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. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value, after the effects of master netting arrangements, of a financial liability or 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. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

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Amount of investment in debt security measured at amortized cost (held-to-maturity).

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Including the current and noncurrent portions, the carrying value of junior subordinated long-term debt owed to unconsolidated subsidiary trusts as of the balance sheet date. Such debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets and was initially scheduled to be repaid after one year or beyond the normal operating cycle if longer.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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The carrying amount as of the balance sheet date for the aggregate of other miscellaneous borrowings owed by the reporting entity.

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Amount, after the effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

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