Fair Value Of Financial Instruments (Schedule Of Estimated Fair Value Of Financial Instruments) (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale securities	$ 9,282,640	$ 8,915,680
Trading securities	15,684	19,993
Non-marketable	93,748	107,324
Securities purchased under agreements to resell	950,000	1,150,000
Interest earning deposits with banks	18,877	707,249
Cash and due from banks	516,509	518,420
Derivative Assets	12,268	12,980
Non-interest bearing deposits	6,413,161	6,750,674
Savings, interest checking and money market deposits	10,085,460	10,108,236
Derivative Liabilities	12,642	13,329
Fair Value Hierarchy, Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	0	0
Derivative Assets	0	0
Derivative Liabilities	0	0
Fair Value Hierarchy, Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	15,684	19,993
Derivative Assets	12,264	12,976
Derivative Liabilities	12,450	13,260
Fair Value Hierarchy, Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	0	0
Derivative Assets	4	4
Derivative Liabilities	192	69
Carrying (Reported) Amount, Fair Value Disclosure [Member] \| Fair Value Hierarchy, Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale securities	540,477	530,342
Federal funds sold	29,490	43,845
Interest earning deposits with banks	18,877	707,249
Cash and due from banks	516,509	518,420
Non-interest bearing deposits	6,413,161	6,750,674
Savings, interest checking and money market deposits	10,085,460	10,108,236
Federal Funds Purchased	175,645	24,795
Carrying (Reported) Amount, Fair Value Disclosure [Member] \| Fair Value Hierarchy, Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale securities	8,610,055	8,257,614
Trading securities	15,684	19,993
Derivative Assets	12,264	12,976
Derivative Liabilities	12,450	13,260
Carrying (Reported) Amount, Fair Value Disclosure [Member] \| Fair Value Hierarchy, Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale securities	132,108	127,724
Non-marketable	93,748	107,324
Securities purchased under agreements to resell	950,000	1,150,000
Derivative Assets	4	4
Time open and certificates of deposits	2,441,215	2,188,438
Securities Sold under Agreements to Repurchase	978,678	1,321,763
Other borrowings	105,096	107,310
Derivative Liabilities	192	69
Carrying (Reported) Amount, Fair Value Disclosure [Member] \| Fair Value Hierarchy, Level 3 [Member] \| Business [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans	4,095,253	3,715,319
Carrying (Reported) Amount, Fair Value Disclosure [Member] \| Fair Value Hierarchy, Level 3 [Member] \| Real Estate - Construction And Land [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans	442,093	406,197
Carrying (Reported) Amount, Fair Value Disclosure [Member] \| Fair Value Hierarchy, Level 3 [Member] \| Real Estate - Business [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans	2,277,898	2,313,550
Carrying (Reported) Amount, Fair Value Disclosure [Member] \| Fair Value Hierarchy, Level 3 [Member] \| Real Estate - Personal [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans	1,819,204	1,787,626
Carrying (Reported) Amount, Fair Value Disclosure [Member] \| Fair Value Hierarchy, Level 3 [Member] \| Consumer [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans	1,637,841	1,512,716
Carrying (Reported) Amount, Fair Value Disclosure [Member] \| Fair Value Hierarchy, Level 3 [Member] \| Revolving Home Equity [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans	423,566	420,589
Carrying (Reported) Amount, Fair Value Disclosure [Member] \| Fair Value Hierarchy, Level 3 [Member] \| Consumer Credit Card [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans	760,289	796,228
Carrying (Reported) Amount, Fair Value Disclosure [Member] \| Fair Value Hierarchy, Level 3 [Member] \| Overdrafts [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans	3,895	4,611
Estimate of Fair Value, Fair Value Disclosure [Member] \| Fair Value Hierarchy, Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale securities	540,477	530,342
Federal funds sold	29,490	43,845
Interest earning deposits with banks	18,877	707,249
Cash and due from banks	516,509	518,420
Non-interest bearing deposits	6,413,161	6,750,674
Savings, interest checking and money market deposits	10,085,460	10,108,236
Federal Funds Purchased	175,645	24,795
Estimate of Fair Value, Fair Value Disclosure [Member] \| Fair Value Hierarchy, Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale securities	8,610,055	8,257,614
Trading securities	15,684	19,993
Derivative Assets	12,264	12,976
Derivative Liabilities	12,450	13,260
Estimate of Fair Value, Fair Value Disclosure [Member] \| Fair Value Hierarchy, Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale securities	132,108	127,724
Non-marketable	93,748	107,324
Securities purchased under agreements to resell	949,766	1,149,625
Derivative Assets	4	4
Time open and certificates of deposits	2,442,040	2,190,610
Securities Sold under Agreements to Repurchase	978,753	1,321,633
Other borrowings	113,686	116,843
Derivative Liabilities	192	69
Estimate of Fair Value, Fair Value Disclosure [Member] \| Fair Value Hierarchy, Level 3 [Member] \| Business [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans	4,106,975	3,723,263
Estimate of Fair Value, Fair Value Disclosure [Member] \| Fair Value Hierarchy, Level 3 [Member] \| Real Estate - Construction And Land [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans	445,999	410,022
Estimate of Fair Value, Fair Value Disclosure [Member] \| Fair Value Hierarchy, Level 3 [Member] \| Real Estate - Business [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans	2,309,972	2,345,124
Estimate of Fair Value, Fair Value Disclosure [Member] \| Fair Value Hierarchy, Level 3 [Member] \| Real Estate - Personal [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans	1,853,736	1,802,364
Estimate of Fair Value, Fair Value Disclosure [Member] \| Fair Value Hierarchy, Level 3 [Member] \| Consumer [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans	1,638,204	1,519,830
Estimate of Fair Value, Fair Value Disclosure [Member] \| Fair Value Hierarchy, Level 3 [Member] \| Revolving Home Equity [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans	427,150	424,811
Estimate of Fair Value, Fair Value Disclosure [Member] \| Fair Value Hierarchy, Level 3 [Member] \| Consumer Credit Card [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans	771,101	811,550
Estimate of Fair Value, Fair Value Disclosure [Member] \| Fair Value Hierarchy, Level 3 [Member] \| Overdrafts [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans	$ 3,895	$ 4,611

Federal Home Loan Bank advances and other borrowings

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Interest Bearing Deposits With Federal Reserve Bank

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Long-term securities purchased under agreements to resell.

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Non-Marketable investments include Federal Home Loan Bank stock, Federal Reserve Bank stock, and private equity investments.

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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

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Amount of short term borrowing where a bank borrows, at the federal funds rate, from another bank.

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The amount outstanding of funds lent to other depository institutions, securities brokers, or securities dealers in the form of Federal Funds sold; for example, immediately available funds lent under agreements or contracts that mature in one business day or roll over under a continuing contract, regardless of the nature of the transaction or the collateral involved, excluding overnight lending for commercial and industrial purposes. Also include Federal Funds sold under agreements to resell on a gross basis, excluding (1) sales of term Federal Funds, (2) due bills representing purchases of securities or other assets by the reporting bank that have not yet been delivered and similar instruments, (3) resale agreements that mature in more than one business day involving assets other than securities, and (4) yield maintenance dollar repurchase agreements.

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The aggregate of all domestic and foreign interest-bearing deposit liabilities.

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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The aggregate amount of all domestic and foreign noninterest-bearing deposits liabilities held by the entity.

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

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Amount of deposits that cannot be withdrawn before a set date without penalty or for which notice of withdrawal is required. Time deposits include, but are not limited to, certificates of deposits, individual retirement accounts and open accounts.

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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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