v3.2.0.727

Derivative Instruments (Detail 5) (Details) - USD ($) $ in Millions | Jun. 30, 2015 | Dec. 31, 2014
--- | --- | ---
Derivative Instruments Subject to Master Netting Arrangement [Line Items] |  |  |
Derivative Asset, Fair Value, Gross Asset |  | $ 2,244 | $ 2,497
Derivative Asset, Fair Value, Amount Not Offset Against Collateral |  | (1,737) | (2,087)
Derivative, Collateral, Obligation to Return Cash | [1] | (187) | (269)
Derivative Liability, Fair Value, Gross Liability |  | (1,860) | (2,226)
Derivative Liability, Fair Value, Amount Not Offset Against Collateral |  | 1,737 | 2,087
Derivative, Collateral, Right to Reclaim Cash | [1] | 9 | 15
Derivative, Fair Value, Net |  | 384 | 271
Derivative Fair Value, Amount Not Offset Against Collateral, Net |  | 0 | 0
Margin/Cash (Received) Posted Subject to Master Netting Arrangement | [1] | (178) | (254)
Derivative Asset, Fair Value, Amount Offset Against Collateral |  | 320 | 141
Derivative Liability, Fair Value, Amount Offset Against Collateral |  | (114) | (124)
Derivative, Fair Value, Amount Offset Against Collateral, Net |  | 206 | 17
Commodity Exchange Traded Futures and Swaps Contracts [Member] |  |  |
Derivative Instruments Subject to Master Netting Arrangement [Line Items] |  |  |
Derivative Asset, Fair Value, Gross Asset |  | 1,684 | 2,134
Derivative Asset, Fair Value, Amount Not Offset Against Collateral |  | (1,506) | (1,865)
Derivative, Collateral, Obligation to Return Cash | [1] | (178) | (269)
Derivative Liability, Fair Value, Gross Liability |  | (1,506) | (1,870)
Derivative Liability, Fair Value, Amount Not Offset Against Collateral |  | 1,506 | 1,865
Derivative, Collateral, Right to Reclaim Cash | [1] | 0 | 5
Derivative Asset, Fair Value, Amount Offset Against Collateral |  | 0 | 0
Derivative Liability, Fair Value, Amount Offset Against Collateral |  | 0 | 0
Commodity Forward Contract [Member] |  |  |
Derivative Instruments Subject to Master Netting Arrangement [Line Items] |  |  |
Derivative Asset, Fair Value, Gross Asset |  | 557 | 359
Derivative Asset, Fair Value, Amount Not Offset Against Collateral |  | (231) | (222)
Derivative, Collateral, Obligation to Return Cash | [1] | (9) | 0
Derivative Liability, Fair Value, Gross Liability |  | (249) | (242)
Derivative Liability, Fair Value, Amount Not Offset Against Collateral |  | 231 | 222
Derivative, Collateral, Right to Reclaim Cash | [1] | 9 | 10
Derivative Asset, Fair Value, Amount Offset Against Collateral |  | 317 | 137
Derivative Liability, Fair Value, Amount Offset Against Collateral |  | (9) | (10)
Interest Rate Swap [Member] |  |  |
Derivative Instruments Subject to Master Netting Arrangement [Line Items] |  |  |
Derivative Asset, Fair Value, Gross Asset |  | 3 | 4
Derivative Asset, Fair Value, Amount Not Offset Against Collateral |  | 0 | 0
Derivative, Collateral, Obligation to Return Cash | [1] | 0 | 0
Derivative Liability, Fair Value, Gross Liability |  | (105) | (114)
Derivative Liability, Fair Value, Amount Not Offset Against Collateral |  | 0 | 0
Derivative, Collateral, Right to Reclaim Cash | [1] | 0 | 0
Derivative, Fair Value, Net |  | (102) | (110)
Derivative Asset, Fair Value, Amount Offset Against Collateral |  | 3 | 4
Derivative Liability, Fair Value, Amount Offset Against Collateral |  | $ (105) | $ (114)
[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 and natural gas and power prepayments 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 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, deducted from 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=51825145&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)(1)(i) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 + Details
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- Definition Fair value, after effects of master netting arrangements, 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 offset against the right to receive collateral. Includes liabilities not subject to a master netting arrangement and not elected to be offset. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=56946850&loc=d3e41678-113959 Reference 2: 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=51825145&loc=SL20226016-175313 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 + Details
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