Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Compensating balance arrangements that do not legally restrict the withdrawal or usage of cash equivalents may be reported as cash equivalents, while legally restricted equivalents held as compensating balances against borrowing arrangements, contracts entered into with others, or company statements of intention with regard to particular equivalents are not generally reported as part of unrestricted cash equivalents.

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

Fair Value Measurements (Schedule Of Carrying Value And Fair Value Measurement Information For Financial Assets And Liabilities) (Details) (USD $) In Millions	Sep. 30, 2011	Dec. 31, 2010	Sep. 30, 2010	Dec. 31, 2009
Investments	$ 84	$ 94	$ 95	$ 115
Derivatives, assets	916	389
Derivatives, liabilities	(58)	(192)
Commodity Derivatives [Member] \| Carrying Amount [Member]
Derivatives, assets	860	249
Derivatives, liabilities	(58)	(192)
Commodity Derivatives [Member] \| Total Fair Value [Member]
Derivatives, assets	860	249
Derivatives, liabilities	(58)	(192)
Commodity Derivatives [Member] \| Level 2 Inputs [Member]
Derivatives, assets	860	249
Derivatives, liabilities	(58)	(192)
Interest Rate Derivatives [Member] \| Carrying Amount [Member]
Derivatives, assets	56	140
Interest Rate Derivatives [Member] \| Total Fair Value [Member]
Derivatives, assets	56	140
Interest Rate Derivatives [Member] \| Level 2 Inputs [Member]
Derivatives, assets	56	140
Short-Term Investments [Member] \| Carrying Amount [Member]
Investments	1,231	145
Short-Term Investments [Member] \| Total Fair Value [Member]
Investments	1,231	145
Short-Term Investments [Member] \| Level 1 Inputs [Member]
Investments	289	145
Short-Term Investments [Member] \| Level 2 Inputs [Member]
Investments	942
Long-Term Investments [Member] \| Carrying Amount [Member]
Investments	84	94
Long-Term Investments [Member] \| Total Fair Value [Member]
Investments	84	94
Long-Term Investments [Member] \| Level 3 Inputs [Member]
Investments	84	94
Carrying Amount [Member]
Cash equivalents	5,161	2,335
Debt	(9,257)	(5,630)
Total Fair Value [Member]
Cash equivalents	5,161	2,355
Debt	(10,625)	(6,629)
Level 1 Inputs [Member]
Cash equivalents	1,262	2,335
Level 2 Inputs [Member]
Cash equivalents	3,899
Debt	(10,533)	(6,485)
Level 3 Inputs [Member]
Debt	$ (92)	$ (144)