v3.4.0.3

Derivative Instruments (Detail 5) (Details) - USD ($) $ in Millions | Mar. 31, 2016 | Dec. 31, 2015
--- | --- | ---
Derivative Instruments Subject to Master Netting Arrangement [Line Items] |  |  |
Derivative Asset, Fair Value, Gross Asset |  | $ 2,273 | $ 2,011
Derivative Asset, Fair Value, Amount Not Offset Against Collateral |  | (2,104) | (1,804)
Derivative, Collateral, Obligation to Return Cash | [1] | (100) | (137)
Derivative Liability, Fair Value, Gross Liability |  | (2,560) | (2,207)
Derivative Liability, Fair Value, Amount Not Offset Against Collateral |  | 2,104 | 1,804
Derivative, Collateral, Right to Reclaim Cash | [1] | 1 | 5
Derivative, Fair Value, Net |  | (287) | (196)
Derivative Fair Value, Amount Not Offset Against Collateral, Net |  | 0 | 0
Margin/Cash (Received) Posted Subject to Master Netting Arrangement | [1] | (99) | (132)
Derivative Asset, Fair Value, Amount Offset Against Collateral |  | 69 | 70
Derivative Liability, Fair Value, Amount Offset Against Collateral |  | (455) | (398)
Derivative, Fair Value, Amount Offset Against Collateral, Net |  | (386) | (328)
Commodity Exchange Traded Futures and Swaps Contracts [Member] |  |  |
Derivative Instruments Subject to Master Netting Arrangement [Line Items] |  |  |
Derivative Asset, Fair Value, Gross Asset |  | 1,967 | 1,736
Derivative Asset, Fair Value, Amount Not Offset Against Collateral |  | (1,874) | (1,602)
Derivative, Collateral, Obligation to Return Cash | [1] | (93) | (134)
Derivative Liability, Fair Value, Gross Liability |  | (1,874) | (1,604)
Derivative Liability, Fair Value, Amount Not Offset Against Collateral |  | 1,874 | 1,602
Derivative, Collateral, Right to Reclaim Cash | [1] | 0 | 2
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 |  | 305 | 274
Derivative Asset, Fair Value, Amount Not Offset Against Collateral |  | (230) | (202)
Derivative, Collateral, Obligation to Return Cash | [1] | (7) | (3)
Derivative Liability, Fair Value, Gross Liability |  | (588) | (513)
Derivative Liability, Fair Value, Amount Not Offset Against Collateral |  | 230 | 202
Derivative, Collateral, Right to Reclaim Cash | [1] | 1 | 3
Derivative Asset, Fair Value, Amount Offset Against Collateral |  | 68 | 69
Derivative Liability, Fair Value, Amount Offset Against Collateral |  | (357) | (308)
Interest Rate Swap [Member] |  |  |
Derivative Instruments Subject to Master Netting Arrangement [Line Items] |  |  |
Derivative Asset, Fair Value, Gross Asset |  | 1 | 1
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 |  | (98) | (90)
Derivative Liability, Fair Value, Amount Not Offset Against Collateral |  | 0 | 0
Derivative, Collateral, Right to Reclaim Cash | [1] | 0 | 0
Derivative, Fair Value, Net |  | (97) | (89)
Derivative Asset, Fair Value, Amount Offset Against Collateral |  | 1 | 1
Derivative Liability, Fair Value, Amount Offset Against Collateral |  | $ (98) | $ (90)
[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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