This item represents the excess of [amortized] cost over fair value of securities that have been in a loss position for twelve months or longer for those securities which are categorized neither as held-to-maturity nor trading securities.

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

-Publisher FASB

-Name Emerging Issues Task Force (EITF)

-Number 03-1

-Paragraph 21

-Subparagraph a(2)

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name FASB Staff Position (FSP)

-Number FAS115-1/124-1

-Paragraph 17

-Subparagraph a(1)

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- Definition

This item represents the excess of [amortized] cost over fair value of securities in a loss position and which are categorized neither as held-to-maturity nor trading securities.

+ References

+ Details

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- Definition

This item represents the fair value of securities in an unrealized loss position which are categorized neither as held-to-maturity nor trading securities.

+ References

+ Details

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- Definition

This item represents the excess of [amortized] cost over fair value of securities that have been in a loss position for less than twelve months for those securities which are categorized neither as held-to-maturity nor trading securities.

+ References

+ Details

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- Definition

This item represents the fair value of securities categorized neither as held-to-maturity nor trading securities that have been in a continuous unrealized loss position for less than twelve months.

+ References

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- Definition

This item represents the fair value of securities categorized neither as held-to-maturity nor trading securities that have been in a continuous unrealized loss position for twelve months or longer.

+ References

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Securities (Details 1) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Dec. 31, 2011	Mar. 31, 2011
Available for Sale Securities (Unrealized Loss Position)
Fair value, less than 12 months	$ 3	$ 4	$ 3,819
Fair value, 12 months or longer
Fair Value	3	4	3,819
Gross unrealized losses, less than 12 months			40
Gross unrealized losses, 12 months or longer
Gross unrealized losses, Total			40
States and political subdivisions [Member]
Available for Sale Securities (Unrealized Loss Position)
Fair value, less than 12 months	1
Fair value, 12 months or longer
Fair Value	1
Gross unrealized losses, 12 months or longer
Collateralized Mortgage Backed Securities [Member]
Available for Sale Securities (Unrealized Loss Position)
Fair value, less than 12 months		1	3,819
Fair value, 12 months or longer
Fair Value		1	3,819
Gross unrealized losses, less than 12 months			40
Gross unrealized losses, 12 months or longer
Gross unrealized losses, Total			40
Other securities [Member]
Available for Sale Securities (Unrealized Loss Position)
Fair value, less than 12 months	2	3
Fair value, 12 months or longer
Fair Value	2	3
Gross unrealized losses, 12 months or longer