FAIR VALUE, Carrying Amounts And Fair Values Of Financial Instruments (Details) (USD $) In Thousands	Sep. 30, 2011	Dec. 31, 2010
Customer deposit accounts [Abstract]
Maximum term of maturity for securities purchased under resale agreements to be included in cash and cash equivalents (in days)	90D
Term of maturity that securities purchased under resale agreements must exceed to be included in certain fair value calculations (in days)	90D
Maximum term of maturity for carrying amount of securities sold under repurchase agreements to approximate fair value (in days)	90D
Carrying Amount or Notional Amount [Member]
Financial Assets [Abstract]
Cash and cash equivalents	$ 1,105,888	$ 1,333,949
Short-term investments	66,009	143,560
Federal funds sold	30,000	0
Securities purchased under resale agreements	951,824	500,000
Investment securities available-for-sale	3,279,592	2,875,941
Loans held for sale	251,920	220,055
Loans receivable, net	13,718,668	13,231,075
Investment in Federal Home Loan Bank stock	143,381	162,805
Investment in Federal Reserve Bank stock	47,384	47,285
Accrued interest receivable	93,042	82,090
Equity swap agreements	22,709	22,884
Foreign exchange options	85,614	85,614
Interest rate swaps	510,898	4,098
Customer deposit accounts [Abstract]
Demand, savings and money market deposits	9,824,307	8,875,806
Time deposits	7,484,393	6,765,453
Federal funds purchased	0	22
Federal Home Loan Bank advances	457,075	1,214,148
Securities sold under repurchase agreements	1,024,949	1,083,545
Notes payable	85,014	49,690
Accrued interest payable	16,352	13,797
Long-term debt	214,178	235,570
Derivative liabilities	486,235	79,640
Estimated Fair Value [Member]
Financial Assets [Abstract]
Cash and cash equivalents	1,105,888	1,333,949
Short-term investments	66,009	143,560
Federal funds sold	30,000	0
Securities purchased under resale agreements	982,118	505,826
Investment securities available-for-sale	3,279,592	2,875,941
Loans held for sale	257,631	225,221
Loans receivable, net	13,284,682	13,043,932
Investment in Federal Home Loan Bank stock	143,381	162,805
Investment in Federal Reserve Bank stock	47,384	47,285
Accrued interest receivable	93,042	82,090
Equity swap agreements	200	206
Foreign exchange options	4,392	5,084
Interest rate swaps	17,791	13
Customer deposit accounts [Abstract]
Demand, savings and money market deposits	9,119,064	7,896,736
Time deposits	7,519,569	6,762,892
Federal funds purchased	0	22
Federal Home Loan Bank advances	489,680	1,199,151
Securities sold under repurchase agreements	1,077,835	1,296,522
Notes payable	85,014	49,690
Accrued interest payable	16,352	13,797
Long-term debt	139,143	125,633
Derivative liabilities	$ 20,206	$ 3,463

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. The element may be used in both the balance sheet and disclosure in the same submission. This item includes interest owed but not yet paid by the entity.

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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. The element may be used in both the balance sheet and disclosure in the same submission. This item includes interest earned but not yet received by the entity.

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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. The element may be used in both the balance sheet and disclosure. This item represents the aggregate of certain deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing, specifically demand deposits, saving deposits, and money market deposits.

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Fair values as of the balance sheet date of all assets resulting from contracts that meet the criteria of being accounted for as equity swap agreements.

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Represents the portion of the balance sheet assertion valued at fair value and may be used in connection with the fair value disclosures required in the footnotes. This is the carrying value of funds outstanding loaned in the form of security resale agreements if the agreement requires the purchaser to resell the identical security purchased or a security meeting the definition of 'substantially the same. This item represents federal funds sold as of the balance sheet date.

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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. The element may be used in both the balance sheet and disclosure in the same submission. This item represents interest rate swap contracts entered into and existing as of the balance sheet date.

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Represents the portion of the balance sheet assertion valued at fair value and may be used in connection with the fair value disclosures required in the footnotes. Federal Reserve Bank stock represents an equity interest in the Federal Reserve Bank.

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The maximum term of original maturity for securities sold under repurchase agreements for which the carrying amounts on the Consolidated Balance Sheet will approximate fair values due to the short-term nature of the instruments.

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The maximum term of original maturity for which securities purchased under resale agreements are included in cash and cash equivalents on the Consolidated Balance Sheet.

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Represents the portion of the balance sheet assertion valued at fair value and may be used in connection with the fair value disclosures required in the footnotes. This is the carrying value of funds outstanding loaned in the form of security resale agreements if the agreement requires the purchaser to resell the identical security purchased or a security meeting the definition of 'substantially the same.' Includes purchases of participations in pools of securities that are subject to a resale agreement.

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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. The element may be used in both the balance sheet and disclosure in the same submission. This item includes investments expected to mature within one year of the balance sheet date.

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The term of original maturity that securities purchased under resale agreements must exceed to be included in certain fair value calculations. The fair value of securities purchased under resale agreements exceeding this term of original maturity is estimated by discounting the cash flows based on expected maturities or repricing dates utilizing estimated market discount rates.

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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. The element may be used in both the balance sheet and disclosure. This item represents the aggregate of certain deposit liabilities held by the entity, including foreign and domestic, interest bearing, specifically time deposits.

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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.

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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Company may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months.

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Derivative instrument obligations meeting the definition of a liability which the Company is a party to as of the balance sheet date.

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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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-Name Statement of Financial Accounting Standard (FAS)

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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. The amount of securities that an institution sells and agrees to repurchase (seller-borrower) at a specified date for a specified price, net of any reductions or offsets. Most repurchase agreements involve obligations of the federal government or its agencies, but other financial instruments, such as commercial paper, banker's acceptances, and negotiable certificates of deposit (CDs), are sometimes used in repurchase agreements. A repurchase agreement is similar to the seller-borrower's borrowing funds equal to the sales price of the related securities with the securities as collateral. Maturities of such agreements are flexible and generally vary from one day to 270 days.

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