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This item represents the excess of amortized cost basis 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.

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

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This item represents the excess of amortized cost basis 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.

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

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The amount of other than temporary impairment losses on investments in debt and equity securities categorized as Available-for-sale which have been recognized in earnings during the period. Such impairment losses consist of other than temporary impairments (OTTI) on equity securities, credit losses on investments in debt securities, and when the entity intends to sell an impaired debt security or it is more likely than not that the entity will be required to sell the impaired debt security before recovery of its amortized cost basis.

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Available-For-Sale Securities (Details 2) (USD $) In Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	Dec. 31, 2010
Available-For-Sale Securities
Pretax charges recognized for "other-than-temporary" declines in the market values of equities securities	$ 1	$ 4	$ 2
Less than 12 months
Fair Value		133		38
Unrealized Losses		13		1
12 months or more
Fair Value		47		70
Unrealized Losses		12		11
Total
Fair Value		180		108
Unrealized Losses		25		12
Corporate bonds
Less than 12 months
Fair Value		65
Unrealized Losses		1
Total
Fair Value		65
Unrealized Losses		1
Asset-backed securities
Less than 12 months
Fair Value				19
12 months or more
Fair Value		17		19
Unrealized Losses		5		4
Total
Fair Value		17		38
Unrealized Losses		5		4
Residential mortgage-backed securities
Less than 12 months
Fair Value				2
12 months or more
Fair Value		18		25
Unrealized Losses		4		4
Total
Fair Value		18		27
Unrealized Losses		4		4
Commercial mortgage-backed securities
Less than 12 months
Fair Value		14		3
Unrealized Losses		2
12 months or more
Fair Value		7		14
Unrealized Losses		2		1
Total
Fair Value		21		17
Unrealized Losses		4		1
Large capitalization value
Less than 12 months
Fair Value		49		14
Unrealized Losses		9		1
12 months or more
Fair Value		5		12
Unrealized Losses		1		2
Total
Fair Value		54		26
Unrealized Losses		10		3
Smaller company growth
Less than 12 months
Fair Value		5
Unrealized Losses		1
Total
Fair Value		5
Unrealized Losses		$ 1