Fair Value Measurement (Schedule Of Carrying Value And Fair Value Of Financial Instruments Not Recorded At Fair Value) (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018	Dec. 31, 2017
FINANCIAL ASSETS:
Equity and other, at fair value	$ 63,327	$ 61,841
Available for sale, at fair value	2,894,778	2,977,108
Investment securities held to maturity	3,478	3,606
Loans held for sale, at fair value	240,302	166,461
Loans and leases, net	20,261,125	20,277,795
Restricted equity securities	47,466	40,268
Residential mortgage servicing rights	158,946	169,025	$ 164,760	$ 153,151
Bank owned life insurance	314,303	313,626
Derivatives	84,090	49,484
FINANCIAL LIABILITIES:
Deposits	21,243,894	21,137,486
Securities sold under agreements to repurchase	288,944	297,151
Term debt	932,420	751,788
Junior subordinated debentures, at fair value	294,121	300,870
Junior subordinated debentures, at amortized cost	88,667	88,724
Derivatives	11,393	15,982
Carrying Value
FINANCIAL ASSETS:
Cash and Cash Equivalents	902,808	622,637
Equity and other, at fair value	63,327	61,841
Available for sale, at fair value	2,894,778	2,977,108
Investment securities held to maturity	3,478	3,606
Loans held for sale, at fair value	240,302	166,461
Loans and leases, net	20,261,125	20,277,795
Restricted equity securities	47,466	40,268
Residential mortgage servicing rights	158,946	169,025
Bank owned life insurance	314,303	313,626
Derivatives	84,090	49,484
Visa Class B common stock	0	0
FINANCIAL LIABILITIES:
Deposits	21,243,894	21,137,486
Securities sold under agreements to repurchase	288,944	297,151
Term debt	932,420	751,788
Junior subordinated debentures, at fair value	294,121	300,870
Junior subordinated debentures, at amortized cost	88,667	88,724
Derivatives	11,393	15,982
Estimated Fair Value
FINANCIAL ASSETS:
Cash and Cash Equivalents	902,808	622,637
Equity and other, at fair value	63,327	61,841
Available for sale, at fair value	2,894,778	2,977,108
Investment securities held to maturity	4,517	4,644
Loans held for sale, at fair value	240,302	166,461
Loans and leases, net	20,200,593	20,117,939
Restricted equity securities	47,466	40,268
Residential mortgage servicing rights	158,946	169,025
Bank owned life insurance	314,303	313,626
Derivatives	84,090	49,484
Visa Class B common stock	117,613	99,353
FINANCIAL LIABILITIES:
Deposits	21,239,390	21,116,852
Securities sold under agreements to repurchase	288,944	297,151
Term debt	923,743	738,107
Junior subordinated debentures, at fair value	294,121	300,870
Junior subordinated debentures, at amortized cost	75,052	76,569
Derivatives	$ 11,393	$ 15,982

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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Other Company Stock Owned

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Term Debt

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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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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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