v3.7.0.1

Derivative Instruments (Details 2) (Details) - USD ($) $ in Millions | Mar. 31, 2017 | Dec. 31, 2016
--- | --- | ---
Derivatives, Fair Value [Line Items] |  |
Derivative assets, current | $ 1,387 | $ 1,725
Long-term derivative assets | 670 | 543
Total derivative assets | 2,057 | 2,268
Derivative liabilities, current | 1,273 | 1,630
Long-term derivative liabilities | 550 | 476
Total derivative liabilities | 1,823 | 2,106
Derivative, Fair Value, Net | 234 | 162
Designated as Hedging Instrument [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Total derivative assets | 37 | 29
Total derivative liabilities | 55 | 58
Not Designated as Hedging Instrument [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Total derivative assets | 2,020 | 2,239
Total derivative liabilities | 1,768 | 2,048
Interest Rate Hedging Instruments |  |
Derivatives, Fair Value [Line Items] |  |
Derivative assets, current | 1 | 1
Derivative Assets, Noncurrent | 36 | 28
Total derivative assets | 37 | 29
Current derivative liabilities | 27 | 28
Derivative Liabilities, Noncurrent | 28 | 30
Total derivative liabilities | 55 | 58
Derivative, Fair Value, Net | (18) | (29)
Interest Rate Hedging Instruments | Designated as Hedging Instrument [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Total derivative assets | 37 | 29
Total derivative liabilities | 55 | 58
Energy Related Derivative [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative assets, current | 1,386 | 1,724
Derivative Assets, Noncurrent | 634 | 515
Total derivative assets | 2,020 | 2,239
Current derivative liabilities | 1,246 | 1,602
Derivative Liabilities, Noncurrent | 522 | 446
Total derivative liabilities | 1,768 | 2,048
Derivative, Fair Value, Net | 252 | 191
Energy Related Derivative [Member] | Not Designated as Hedging Instrument [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Total derivative assets | 2,020 | 2,239
Total derivative liabilities | $ 1,768 | $ 2,048

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