Fair Value Measurements (Assets and Liabilities that are Measured at Fair Value on a Recurring Basis) (Details) (USD $) In Millions	Jun. 30, 2011	Dec. 31, 2010
Money market funds	$ 942	$ 3,337
Available-for-sale investments	9	15
Derivatives, assets	260	227
Total assets	1,211	3,579
Derivatives, liabilities	(114)	(115)
Total liabilities	(114)	(115)
Level 1 [Member]
Money market funds	942	3,337
Available-for-sale investments	5	10
Derivatives, assets
Total assets	947	3,347
Derivatives, liabilities
Total liabilities
Level 2 [Member]
Money market funds
Available-for-sale investments
Derivatives, assets	260	227
Total assets	260	227
Derivatives, liabilities	(114)	(115)
Total liabilities	(114)	(115)
Level 3 [Member]
Money market funds
Available-for-sale investments	4	5
Derivatives, assets
Total assets	4	5
Derivatives, liabilities
Total liabilities

Fair values as of the balance sheet date of all assets resulting from contracts that meet the criteria of being accounted for as derivative instruments, net of the effects of master netting arrangements.

+ References+ Details

Derivative instrument obligations meeting the definition of a liability which the Company is a party to as of the balance sheet date.

+ References+ Details

- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents investment securities as of the balance sheet date which may include marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References+ Details