Securities (Details Textual) (USD $)	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Securities (Textual) [Abstract]
Held-to-maturity Securities	$ 0	$ 0
Trading securities	0	0
Proceeds and pay downs of available for sale securities	342,900,000	300,000	11,700,000
Securities pledged to secure public deposits and securities sold under agreements to repurchase	$ 3,000,000,000	$ 1,300,000,000

For an unclassified balance sheet, this item represents investments in debt securities which are categorized as held-to-maturity. The held-to-maturity category is for those securities that the entity has the positive intent and ability to hold until maturity.

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

-Publisher FASB

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-Name Accounting Research Bulletin (ARB)

-Number 43

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+ Details

- Definition

The total of financial instruments that are bought and held principally for the purpose of selling them in the near term (thus held for only a short period of time) or for debt and equity securities formerly categorized as available-for-sale or held-to-maturity which the entity held as of the date it opted to account for such securities at fair value. An enterprise may also categorize such a security as trading without the intent to sell it in the near term assuming the decision to categorize the security as trading occurred at acquisition.

+ References

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

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-Name Accounting Standards Codification

-Glossary Trading Securities

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