Securities (Details Textual) (USD $)	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010
Securities (Textuals) [Abstract]
Sales of mortgage-backed securities available for sale	$ 8,960,000,000	$ 1,090,000,000
Realized gains on sale of mortgage-backed securities available for sale	100,000,000	61,400,000
Sales of investment securities held to maturity	0
Gross realized gains on sales and calls of investment securities available for sale	2,500,000
Sales of investment securities available-for-sale	$ 80,000,000

Gross realized gains on sales and calls of investment securities available for sale.

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- Definition

Principle amount of investment securities available for sale.

+ Details

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- Definition

Sales of mortgage-backed securities available for sale.

+ Details

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- Definition

Securities Textuals.

+ Details

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- Definition

This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 21
-Subparagraph a

+ Details

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- Definition

The total amount of proceeds received for the sale of securities, categorized neither as held-to-maturity nor trading securities, during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 21
-Subparagraph a

+ Details

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