FAIR VALUE DISCLOSURES, Carrying and Fair Value Information (Details) (USD $) In Thousands	Sep. 30, 2011	Dec. 31, 2010
Carrying Value [Member]
Assets:
Cash and due from banks	$ 161,876	$ 99,916
Interest bearing deposits with other banks	338,250	172,170
Held-to-maturity securities	0	1,613,019
Available-for-sale securities	2,481,555	1,096,062
Federal funds sold and securities purchased under agreement to resell	0	150,000
Net loans and leases	8,856,219	9,136,194
Loans held for sale	100,687	93,697
Liabilities:
Noninterest bearing deposits	2,198,535	2,060,145
Savings and interest bearing deposits	5,705,135	5,794,552
Other time deposits	3,159,563	3,635,324
Federal funds purchased and securities sold under agreement to repurchase and other short-term borrowings	451,001	443,320
Long-term debt and other borrowings	193,883	270,392
Derivative instruments:
Forward commitments to sell fixed rate mortgage loans	(2,391)	2,499
Commitments to fund fixed rate mortgage loans	3,948	639
Interest rate swap position to receive	55,755	38,347
Interest rate swap position to pay	(56,525)	(38,800)
Fair Value [Member]
Assets:
Cash and due from banks	161,876	99,916
Interest bearing deposits with other banks	338,250	172,170
Held-to-maturity securities	0	1,632,691
Available-for-sale securities	2,481,555	1,096,062
Federal funds sold and securities purchased under agreement to resell	0	150,000
Net loans and leases	8,927,062	9,187,064
Loans held for sale	100,955	94,001
Liabilities:
Noninterest bearing deposits	2,198,535	2,060,145
Savings and interest bearing deposits	5,705,135	5,794,552
Other time deposits	3,205,735	3,677,796
Federal funds purchased and securities sold under agreement to repurchase and other short-term borrowings	450,636	443,081
Long-term debt and other borrowings	200,328	286,993
Derivative instruments:
Forward commitments to sell fixed rate mortgage loans	(2,391)	2,499
Commitments to fund fixed rate mortgage loans	3,948	639
Interest rate swap position to receive	55,755	38,347
Interest rate swap position to pay	$ (56,525)	$ (38,800)

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This element represents the portion of the balance sheet assertion valued at fair value by the entity related to forward commitments obtained to sell fixed rate mortgage loans.

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This element represents the portion of the balance sheet assertion valued at fair value by the entity for interest bearing deposits held with other banks.

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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity related to interest rate swap positions to pay on customer related derivative financial instruments.

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This element represents the portion of the balance sheet assertion valued at fair value by the entity related to interest rate swap positions to receive on customer related derivative financial instruments.

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This element represents the portion of the balance sheet assertion valued at fair value by the entity for noninterest bearing deposits held by the company.

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This element represents the portion of the balance sheet assertion valued at fair value by the entity for other time deposits held by the company.

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This element represents the portion of the balance sheet assertion valued at fair value by the entity for savings and interest bearing deposits held by the company.

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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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-Name Statement of Financial Accounting Standard (FAS)

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-Paragraph 12

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- Definition

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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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher AICPA

-Name Audit and Accounting Guide (AAG)

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-Paragraph 4

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-Publisher FASB

-Name Accounting Standards Codification

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-Topic 310

-SubTopic 10

-URI http://asc.fasb.org/extlink&oid=6517073

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- Definition

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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