v2.4.0.6

Risk Management Energy Commodity Price Risk Managment (Details) | Mar. 31, 2013
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Crude Oil [Member] |
Derivative [Line Items] |
Net open position long/(short) | (3,600,000)
Natural Gas Fixed Price [Member] |
Derivative [Line Items] |
Net open position long/(short) | (33,900,000,000)
Net open position long/(short) | (2,000,000,000)
Natural Gas Basis [Member] |
Derivative [Line Items] |
Net open position long/(short) | (34,400,000,000)
Net open position long/(short) | 13,100,000,000
Crude Oil Fixed Price [Member] |
Derivative [Line Items] |
Net open position long/(short) | (21,400,000)
Net open position long/(short) | (100,000)

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- Definition Aggregate notional amount of price risk derivatives not designated as a hedging instrument with notional amounts expressed in nonmonetary units. For example the number of barrels specified in a fuel oil forward purchase 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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