The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

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The portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments representing (a) the amount of the hedge ineffectiveness and (b) the amount, if any, excluded from the assessment of hedge effectiveness.

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The amount of net gains and losses recognized in income during the period on derivative instruments designated and qualifying as hedging instruments in fair value hedges and related hedged items designated and qualifying in fair value hedges, on derivative instruments designated and qualifying as hedging instruments in cash flow hedges, and on derivative instruments not designated as hedging instruments.

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The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

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Net gain (loss) recognized in earnings during the reporting period representing the amount of the fair value of the hedges' ineffectiveness.

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Effect of Derivative Instruments on Statements of Income [Abstract]

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Price Risk Management Activities, Gain (Loss) by Income Statement Location (Details) (USD $) In Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Commodity Contract [Member] \| Fair Value Hedging [Member] \| Cost of Sales [Member]
Effect of Derivative Instruments on Statements of Income
Amount of gain or (loss) recognized in income on derivatives	$ 170	$ 54	$ 219	$ 253
Amount of gain or (loss) recognized in income for ineffective portion of derivative	9	(2)	(3)	6
Commodity Contract [Member] \| Cash Flow Hedging [Member]
Effect of Derivative Instruments on Statements of Income
Amount of gain or (loss) recognized in OCI on derivatives (effective portion)	20	0	20	(2)
Commodity Contract [Member] \| Cash Flow Hedging [Member] \| Cost of Sales [Member]
Effect of Derivative Instruments on Statements of Income
Amount of gain or (loss) reclassified from accumulated OCI into income (effective portion)	0	37	0	135
Amount of gain or (loss) recognized in income on derivatives (ineffective portion)	4	0	4	0
Future [Member] \| Commodity Contract [Member] \| Economic Hedging [Member] \| Cost of Sales [Member]
Effect of Derivative Instruments on Statements of Income
Amount of gain or (loss) recognized in income on derivatives			(542)
Commodity Contract [Member] \| Economic Hedging [Member] \| Cost of Sales [Member]
Effect of Derivative Instruments on Statements of Income
Amount of gain or (loss) recognized in income on derivatives	9	22	(362)	(93)
Economic Hedging [Member]
Effect of Derivative Instruments on Statements of Income
Amount of gain or (loss) recognized in income on derivatives	79	17	(301)	(95)
Economic Hedging [Member] \| Foreign Currency Contract [Member] \| Cost of Sales [Member]
Effect of Derivative Instruments on Statements of Income
Amount of gain or (loss) recognized in income on derivatives	41	(5)	32	(2)
Economic Hedging [Member] \| Other Contract [Member] \| Cost of Sales [Member]
Effect of Derivative Instruments on Statements of Income
Amount of gain or (loss) recognized in income on derivatives	29	0	29	0
Commodity Contract [Member] \| Trading Derivatives [Member] \| Cost of Sales [Member]
Effect of Derivative Instruments on Statements of Income
Amount of gain or (loss) recognized in income on derivatives	3	2	17	7
Commodity Contract [Member] \| Cost of Sales [Member]
Effect of Derivative Instruments on Statements of Income
Amount of gain or (loss) recognized in income on derivatives	$ (161)	$ (56)	$ (222)	$ (247)