Investments (Investment Income (Loss), Net) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2012	Mar. 31, 2011
Investments
Gains on sales and exchanges of investments, net	$ 7	$ 14
Investment impairment losses	(12)	0
Unrealized gains (losses) on securities underlying prepaid forward sale agreements	516	309
Mark to market adjustments on derivative component of prepaid forward sale agreements and indexed debt instruments	470	261
Interest and dividend income	29	26
Other, net	(22)	(1)
Investment income (loss), net	$ 92	$ 89

The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

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+ Details

- Definition

Income derived from investments in debt and equity securities and on cash and cash equivalents. Interest income represents earnings which reflect the time value of money or transactions in which the payments are for the use or forbearance of money. Dividend income represents a distribution of earnings to shareholders by investee companies.

+ References+ Details