v2.4.0.8

Risk Management Fair Value of Derivative Contracts (Details) (USD $) In Millions, unless otherwise specified | Mar. 31, 2014 | Dec. 31, 2013
--- | --- | ---
Derivatives, Fair Value [Line Items] |  |
Derivative Asset, Fair Value, Net | $ 343 | $ 357
Derivative Liability, Fair Value, Net | (274) | (311)
Designated as Hedging Contracts [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative Asset, Fair Value, Net | 327 | 335
Derivative Liability, Fair Value, Net | (158) | (179)
Not Designated as Hedging Instrument [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative Asset, Fair Value, Net | 16 | 22
Derivative Liability, Fair Value, Net | (116) | (132)
Commodity Contract [Member] | Designated as Hedging Contracts [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative Asset, Fair Value, Net | 35 | 76
Derivative Liability, Fair Value, Net | (64) | (63)
Commodity Contract [Member] | Designated as Hedging Contracts [Member] | Current-Fair value of derivative contracts [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative Asset, Fair Value, Net | 13 | 18
Commodity Contract [Member] | Designated as Hedging Contracts [Member] | Other Current Liabilities [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative Liability, Fair Value, Net | (51) | (33)
Commodity Contract [Member] | Designated as Hedging Contracts [Member] | Non-current-Fair value of derivative contracts [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative Asset, Fair Value, Net | 22 | 58
Commodity Contract [Member] | Designated as Hedging Contracts [Member] | Non Current Liabilities [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative Liability, Fair Value, Net | (13) | (30)
Commodity Contract [Member] | Not Designated as Hedging Instrument [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative Asset, Fair Value, Net | 6 | 4
Derivative Liability, Fair Value, Net | (9) | (5)
Commodity Contract [Member] | Not Designated as Hedging Instrument [Member] | Current-Fair value of derivative contracts [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative Asset, Fair Value, Net | 6 | 4
Commodity Contract [Member] | Not Designated as Hedging Instrument [Member] | Other Current Liabilities [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative Liability, Fair Value, Net | (9) | (5)
Interest Rate Swap [Member] | Designated as Hedging Contracts [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative Asset, Fair Value, Net | 292 | 259
Derivative Liability, Fair Value, Net | (94) | (116)
Power Derivative Contract [Member] | Not Designated as Hedging Instrument [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative Asset, Fair Value, Net | 10 | 18
Derivative Liability, Fair Value, Net | (107) | (127)
Power Derivative Contract [Member] | Not Designated as Hedging Instrument [Member] | Current-Fair value of derivative contracts [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative Asset, Fair Value, Net | 2 | 7
Power Derivative Contract [Member] | Not Designated as Hedging Instrument [Member] | Other Current Liabilities [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative Liability, Fair Value, Net | (49) | (54)
Power Derivative Contract [Member] | Not Designated as Hedging Instrument [Member] | Non-current-Fair value of derivative contracts [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative Asset, Fair Value, Net | 8 | 11
Power Derivative Contract [Member] | Not Designated as Hedging Instrument [Member] | Non Current Liabilities [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative Liability, Fair Value, Net | (58) | (73)
Fair Value Hedging [Member] | Interest Rate Swap [Member] | Designated as Hedging Contracts [Member] | Current-Fair value of derivative contracts [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative Asset, Fair Value, Net | 122 | 87
Fair Value Hedging [Member] | Interest Rate Swap [Member] | Designated as Hedging Contracts [Member] | Other Current Liabilities [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative Liability, Fair Value, Net | 0 | 0
Fair Value Hedging [Member] | Interest Rate Swap [Member] | Designated as Hedging Contracts [Member] | Non-current-Fair value of derivative contracts [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative Asset, Fair Value, Net | 170 | 172
Fair Value Hedging [Member] | Interest Rate Swap [Member] | Designated as Hedging Contracts [Member] | Non Current Liabilities [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative Liability, Fair Value, Net | (94) | (116)
Interest Rate Swap [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative Asset, Fair Value, Net | 248 | 231
Interest Rate Swap [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative Liability, Fair Value, Net | $ (50) | $ (88)

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- Definition Fair value of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, elected not to be offset against an obligation to return collateral under a master netting arrangement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=20225523&loc=SL20225862-175312 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=7476318&loc=d3e41678-113959 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=28370219&loc=SL20226011-175313 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=28370219&loc=SL20226006-175313 + Details
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- Definition Fair value of financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, elected not to be offset against a right to receive collateral under a master netting arrangement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=20225523&loc=SL20225862-175312 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=7476318&loc=d3e41678-113959 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=28370219&loc=SL20226011-175313 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=28370219&loc=SL20226006-175313 + Details
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