v2.4.0.8

Derivative Instruments (Detail 5) (Details) (USD $) In Millions, unless otherwise specified | Dec. 31, 2013 | Dec. 31, 2012
--- | --- | ---
Derivative [Line Items] |  |  |  |
Derivative Asset, Fair Value, Gross Asset | $ 550 |  | $ 437 |
Derivative Asset, Fair Value, Amount Not Offset Against Collateral | (480) |  | (396) |
Derivative, Collateral, Obligation to Return Cash | 14 | [1] | 7 | [1]
Derivative Asset, Fair Value, Amount Offset Against Collateral | 56 |  | 34 |
Derivative Liability, Fair Value, Gross Liability | 694 |  | 650 |
Derivative Liability, Fair Value, Amount Not Offset Against Collateral | 480 |  | 396 |
Derivative, Collateral, Right to Reclaim Cash | 76 | [1] | 46 | [1]
Derivative Liability, Fair Value, Amount Offset Against Collateral | 138 |  | 208 |
Derivative, Fair Value, Net | (144) |  | (213) |
Derivative Fair Value, Amount Not Offset Against Collateral, Net | 0 |  | 0 |
Derivative, Collateral, Right to Reclaim Cash, Net | 62 | [1] | 39 | [1]
Derivative, Fair Value, Amount Offset Against Collateral, Net | (82) |  | (174) |
Commodity Option [Member] |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative Asset, Fair Value, Gross Asset | 541 |  | 433 |
Derivative Liability, Fair Value, Gross Liability | 565 |  | 450 |
Derivative, Fair Value, Net | (24) |  | (17) |
Commodity Exchange Traded Futures and Swaps Contracts [Member] |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative Asset, Fair Value, Gross Asset | 434 |  | 385 |
Derivative Asset, Fair Value, Amount Not Offset Against Collateral | (420) |  | (379) |
Derivative, Collateral, Obligation to Return Cash | 14 | [1] | 6 | [1]
Derivative Asset, Fair Value, Amount Offset Against Collateral | 0 |  | 0 |
Derivative Liability, Fair Value, Gross Liability | 495 |  | 424 |
Derivative Liability, Fair Value, Amount Not Offset Against Collateral | 420 |  | 379 |
Derivative, Collateral, Right to Reclaim Cash | 75 | [1] | 45 | [1]
Derivative Liability, Fair Value, Amount Offset Against Collateral | 0 |  | 0 |
Commodity Forward Contract [Member] |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative Asset, Fair Value, Gross Asset | 107 |  | 48 |
Derivative Asset, Fair Value, Amount Not Offset Against Collateral | (60) |  | (17) |
Derivative, Collateral, Obligation to Return Cash | 0 | [1] | 1 | [1]
Derivative Asset, Fair Value, Amount Offset Against Collateral | 47 |  | 30 |
Derivative Liability, Fair Value, Gross Liability | 70 |  | 26 |
Derivative Liability, Fair Value, Amount Not Offset Against Collateral | 60 |  | 17 |
Derivative, Collateral, Right to Reclaim Cash | 1 | [1] | 1 | [1]
Derivative Liability, Fair Value, Amount Offset Against Collateral | 9 |  | 8 |
Interest Rate Swap [Member] |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative Asset, Fair Value, Gross Asset | 9 |  | 4 |
Derivative Asset, Fair Value, Amount Not Offset Against Collateral | 0 |  | 0 |
Derivative, Collateral, Obligation to Return Cash | 0 | [1] | 0 | [1]
Derivative Asset, Fair Value, Amount Offset Against Collateral | 9 |  | 4 |
Derivative Liability, Fair Value, Gross Liability | 129 |  | 200 |
Derivative Liability, Fair Value, Amount Not Offset Against Collateral | 0 |  | 0 |
Derivative, Collateral, Right to Reclaim Cash | 0 | [1] | 0 | [1]
Derivative Liability, Fair Value, Amount Offset Against Collateral | 129 |  | 200 |
Derivative, Fair Value, Net | $ (120) |  | $ (196) |
[1] | Negative balances represent margin deposits posted with us by our counterparties related to our derivative activities that are subject to a master netting arrangement. Positive balances reflect margin deposits posted by us with our counterparties related to our derivative activities that are subject to a master netting arrangement. See Note 9 for a further discussion of our collateral.

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- Definition Amount of obligation to return cash collateral under master netting arrangements that have not been offset against derivative assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=28370219&loc=SL20226016-175313 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (d)(2) -URI http://asc.fasb.org/extlink&oid=20225523&loc=SL20225862-175312 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7476318&loc=d3e41678-113959 + Details
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