v2.4.0.6

Financial Instruments and Derivative Contracts - Net Exposures from Outstanding Derivative Contracts (Detail) In Millions, unless otherwise specified | Dec. 31, 2011 USD ($) | Dec. 31, 2011 EUR (€) | Dec. 31, 2010 USD ($) | Dec. 31, 2010 EUR (€) | Dec. 31, 2011 Commodity derivative [Member] Crude oil, refined products and natural gas liquids [Member] MMBbls | Dec. 31, 2010 Commodity derivative [Member] Crude oil, refined products and natural gas liquids [Member] MMBbls | Dec. 31, 2011 Commodity derivative [Member] Natural gas and power, Fixed price [Member] MMcf | Dec. 31, 2010 Commodity derivative [Member] Natural gas and power, Fixed price [Member] MMcf | Dec. 31, 2011 Commodity derivative [Member] Natural gas and power, Basis [Member] MMcf | Dec. 31, 2010 Commodity derivative [Member] Natural gas and power, Basis [Member] MMcf
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Derivative Instruments [Line Items] |  |  |  |  |  |  |  |  |  |
Open Position Long (Short) |  |  |  |  | (13) | (16) | (57,000) | (69,000) | (25,000) | (43,000)
Sell U.S. dollar, buy other currencies | $ 1,949 |  | $ 569 |  |  |  |  |  |  |
Sell euro, buy other currencies |  | € 61 |  | € 253 |  |  |  |  |  |

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- Definition Aggregate notional amount of all foreign currency derivatives not designated as hedging instruments. Notional amount refers to the number of currency units specified in the foreign currency derivative contract. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5579245-113959 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Notional Amount -URI http://asc.fasb.org/extlink&oid=6519104 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5580258-113959 + Details
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- Definition Aggregate notional amount of foreign currency derivatives to purchase a foreign currency. Notional amount refers to the number of currency units specified in the foreign currency derivative contract. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5579245-113959 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Notional Amount -URI http://asc.fasb.org/extlink&oid=6519104 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5580258-113959 + Details
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