Fair Value Measurement (Schedule Of Carrying Value And Fair Value Of Financial Instruments Not Recorded At Fair Value) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
FINANCIAL ASSETS:
Cash and cash equivalents	$ 277,645	$ 282,455
Trading securities	9,586	9,999
Investment securities available for sale	2,522,539	2,298,555
Investment securities held to maturity	4,609	5,211
Loans held for sale, at fair value	363,275	286,802
Loans and leases, net	16,847,360	15,327,732
Restricted equity securities	46,949	119,334
Residential mortgage servicing rights	131,817	117,259	$ 47,765	$ 27,428
Bank owned life insurance	291,892	294,296
FDIC indemnification asset	855	4,417
Derivatives	43,549	29,210
FINANCIAL LIABILITIES:
Deposits	17,707,189	16,892,099	$ 9,117,660
Securities sold under agreements to repurchase	304,560	313,321
Term debt	888,769	1,006,395
Junior subordinated debentures, at amortized cost	101,254	101,576
Carrying Value [Member]
FINANCIAL ASSETS:
Cash and cash equivalents	773,725	1,605,171
Trading securities	9,586	9,999
Investment securities available for sale	2,522,539	2,298,555
Investment securities held to maturity	4,609	5,211
Loans held for sale, at fair value	363,275	286,802
Loans and leases, net	16,717,038	15,211,565
Restricted equity securities	46,949	119,334
Residential mortgage servicing rights	131,817	117,259
Bank owned life insurance	291,892	294,296
FDIC indemnification asset	855	4,417
Derivatives	43,549	29,775
Visa Class B common stock	0	0
FINANCIAL LIABILITIES:
Deposits	17,707,189	16,892,099
Securities sold under agreements to repurchase	304,560	313,321
Term debt	888,769	1,006,395
Junior subordinated debentures, at fair value	255,457	249,294
Junior subordinated debentures, at amortized cost	101,254	101,576
Derivatives	41,514	30,888
Estimated Fair Value [Member]
FINANCIAL ASSETS:
Cash and cash equivalents	773,725	1,605,171
Trading securities	9,586	9,999
Investment securities available for sale	2,522,539	2,298,555
Investment securities held to maturity	5,590	5,554
Loans held for sale, at fair value	363,275	286,802
Loans and leases, net	16,641,903	15,252,083
Restricted equity securities	46,949	119,334
Residential mortgage servicing rights	131,817	117,259
Bank owned life insurance	291,892	294,296
FDIC indemnification asset	201	2,058
Derivatives	43,549	29,775
Visa Class B common stock	58,751	49,663
FINANCIAL LIABILITIES:
Deposits	17,709,555	16,893,890
Securities sold under agreements to repurchase	304,560	313,321
Term debt	890,852	1,018,948
Junior subordinated debentures, at fair value	255,457	249,294
Junior subordinated debentures, at amortized cost	75,654	73,840
Derivatives	$ 41,514	$ 30,888

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 and equity securities categorized neither as held-to-maturity nor trading.

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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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For banks and other depository institutions: Includes cash on hand (currency and coin), cash items in process of collection, noninterest bearing deposits due from other financial institutions (including corporate credit unions), and noninterest bearing balances with the Federal Reserve Banks, Federal Home Loan Banks and central banks.

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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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Carrying amount of receivable assets originating from the indemnification agreement with the Federal Deposit Insurance Corporation (FDIC), in which the FDIC is to partially cover losses.

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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 after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as 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 before allowance and after 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.

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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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Amount of investments in debt and equity securities and other forms of securities that provide ownership interests classified as trading.

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