Fair Value Measurement (Schedule Of Carrying Value And Fair Value Of Financial Instruments Not Recorded At Fair Value) (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Financial assets:
Equity and other investment securities	$ 80,797	$ 80,165
Investment securities available for sale	2,890,475	2,814,682
Investment securities held to maturity	3,200	3,260
Loans held for sale, at fair value	481,541	513,431
Loans and leases, net	20,960,058	21,038,055
Restricted equity securities	58,062	46,463
Residential mortgage servicing rights	94,346	115,010	$ 158,946	$ 169,025
Bank owned life insurance	322,717	320,611
Derivatives	383,884	150,574
Financial liabilities:
Deposits	22,699,375	22,481,504
Securities sold under agreements to repurchase	346,245	311,308
Borrowings	1,196,597	906,635
Junior subordinated debentures, at fair value	195,521	274,812
Junior subordinated debentures, at amortized cost	88,439	88,496
Derivatives	34,820	8,808
Carrying Value
Financial assets:
Cash and cash equivalents	1,657,716	1,362,756
Equity and other investment securities	80,797	80,165
Investment securities available for sale	2,890,475	2,814,682
Investment securities held to maturity	3,200	3,260
Loans held for sale, at fair value	481,541	513,431
Loans and leases, net	20,960,058	21,038,055
Restricted equity securities	58,062	46,463
Residential mortgage servicing rights	94,346	115,010
Bank owned life insurance	322,717	320,611
Derivatives	383,884	150,574
Financial liabilities:
Deposits	22,699,375	22,481,504
Securities sold under agreements to repurchase	346,245	311,308
Borrowings	1,196,597	906,635
Junior subordinated debentures, at fair value	195,521	274,812
Junior subordinated debentures, at amortized cost	88,439	88,496
Derivatives	34,820	8,808
Fair Value
Financial assets:
Cash and cash equivalents	1,657,716	1,362,756
Equity and other investment securities	80,797	80,165
Investment securities available for sale	2,890,475	2,814,682
Investment securities held to maturity	4,065	4,263
Loans held for sale, at fair value	481,541	513,431
Loans and leases, net	21,347,804	21,274,319
Restricted equity securities	58,062	46,463
Residential mortgage servicing rights	94,346	115,010
Bank owned life insurance	322,717	320,611
Derivatives	383,884	150,574
Financial liabilities:
Deposits	22,754,353	22,503,916
Securities sold under agreements to repurchase	346,245	311,308
Borrowings	1,203,538	906,160
Junior subordinated debentures, at fair value	195,521	274,812
Junior subordinated debentures, at amortized cost	54,020	70,909
Derivatives	$ 34,820	$ 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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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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