Marketable Securities (Details 1) (USD $) In Millions	6 Months Ended
Jun. 30, 2011
Marketable Securities (Textuals)
Proceeds received from sales and maturities of marketable securities	$ 176
Contractual maturities of marketable securities
Due in 1 year or less, amortized cost	158
Due in 1 year or less, fair value	158
Due in 1-5 years, amortized cost	165
Due in 1-5 years, fair value	165
Due in more than 5 years, amortized cost	0
Due in more than 5 years fair Value	0
Marketable securities, amortized cost	323
Available For Sale Debt Securities Fair Value	$ 323

This item represents the total of debt securities at fair value, which are categorized neither as held-to-maturity nor trading securities.

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This item represents debt securities, at cost, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments, as defined), and fair value hedge accounting adjustments, if any, which are expected to mature after five years and through ten years from the balance sheet date and which are categorized neither as held-to-maturity nor trading securities.

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The cash inflow associated with the sale of debt securities classified as available-for-sale securities.

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