v2.4.0.8

Derivative Instruments (Detail 5) (Details) (USD $) In Millions, unless otherwise specified | Mar. 31, 2014 | Dec. 31, 2013
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Derivative Instruments Subject to Master Netting Arrangement [Line Items] |  |  |  |
Derivative, Fair Value, Gross Amount Not Offset Against Collateral, Net | $ (129) |  | $ (144) |
Derivative Fair Value, Amount Not Offset Against Collateral, Net | 0 |  | 0 |
Derivative Asset, Fair Value, Amount Offset Against Collateral | 34 |  | 56 |
Derivative Asset, Fair Value, Gross Asset | 829 |  | 550 |
Derivative Asset, Fair Value, Amount Not Offset Against Collateral | (747) |  | (480) |
Derivative Liability, Fair Value, Gross Liability | (958) |  | (694) |
Derivative Liability, Fair Value, Amount Not Offset Against Collateral | 747 |  | 480 |
Margin/Cash (Received) Posted Subject to Master Netting Arrangement | (26) | [1] | 62 | [1]
Derivative Liability, Fair Value, Amount Offset Against Collateral | (189) |  | (138) |
Derivative, Fair Value, Amount Offset Against Collateral, Net | (155) |  | (82) |
Derivative, Collateral, Right to Reclaim Cash | 22 | [1] | 76 | [1]
Derivative, Collateral, Obligation to Return Cash | (48) | [1] | (14) | [1]
Commodity Exchange Traded Futures and Swaps Contracts [Member] |  |  |  |
Derivative Instruments Subject to Master Netting Arrangement [Line Items] |  |  |  |
Derivative Asset, Fair Value, Amount Offset Against Collateral | 0 |  | 0 |
Derivative Asset, Fair Value, Gross Asset | 717 |  | 434 |
Derivative Asset, Fair Value, Amount Not Offset Against Collateral | (669) |  | (420) |
Derivative Liability, Fair Value, Gross Liability | (684) |  | (495) |
Derivative Liability, Fair Value, Amount Not Offset Against Collateral | 669 |  | 420 |
Derivative Liability, Fair Value, Amount Offset Against Collateral | 0 |  | 0 |
Derivative, Collateral, Right to Reclaim Cash | 15 | [1] | 75 | [1]
Derivative, Collateral, Obligation to Return Cash | (48) | [1] | (14) | [1]
Commodity Forward Contract [Member] |  |  |  |
Derivative Instruments Subject to Master Netting Arrangement [Line Items] |  |  |  |
Derivative Asset, Fair Value, Amount Offset Against Collateral | 27 |  | 47 |
Derivative Asset, Fair Value, Gross Asset | 105 |  | 107 |
Derivative Asset, Fair Value, Amount Not Offset Against Collateral | (78) |  | (60) |
Derivative Liability, Fair Value, Gross Liability | (148) |  | (70) |
Derivative Liability, Fair Value, Amount Not Offset Against Collateral | 78 |  | 60 |
Derivative Liability, Fair Value, Amount Offset Against Collateral | (63) |  | (9) |
Derivative, Collateral, Right to Reclaim Cash | 7 | [1] | 1 | [1]
Derivative, Collateral, Obligation to Return Cash | 0 | [1] | 0 | [1]
Interest Rate Swap [Member] |  |  |  |
Derivative Instruments Subject to Master Netting Arrangement [Line Items] |  |  |  |
Derivative, Fair Value, Gross Amount Not Offset Against Collateral, Net | (119) |  | (120) |
Derivative Asset, Fair Value, Amount Offset Against Collateral | 7 |  | 9 |
Derivative Asset, Fair Value, Gross Asset | 7 |  | 9 |
Derivative Asset, Fair Value, Amount Not Offset Against Collateral | 0 |  | 0 |
Derivative Liability, Fair Value, Gross Liability | (126) |  | (129) |
Derivative Liability, Fair Value, Amount Not Offset Against Collateral | 0 |  | 0 |
Derivative Liability, Fair Value, Amount Offset Against Collateral | (126) |  | (129) |
Derivative, Collateral, Right to Reclaim Cash | 0 | [1] | 0 | [1]
Derivative, Collateral, Obligation to Return Cash | $ 0 | [1] | $ 0 | [1]
[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 7 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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