v3.4.0.3
Derivative Instruments (Details 2) (Details) - USD ($)
$ in Millions
Mar. 31, 2016
Dec. 31, 2015
Derivatives, Fair Value [Line Items]    
Derivative assets, current $ 1,853 $ 1,698
Long-term derivative assets 420 313
Total derivative assets 2,273 2,011
Derivative liabilities, current 1,975 1,734
Long-term derivative liabilities 585 473
Total derivative liabilities 2,560 2,207
Derivative, Fair Value, Net (287) (196)
Designated as Hedging Instrument [Member]    
Derivatives, Fair Value [Line Items]    
Total derivative assets 1 1
Total derivative liabilities 100 92
Not Designated as Hedging Instrument [Member]    
Derivatives, Fair Value [Line Items]    
Total derivative assets 2,272 2,010
Total derivative liabilities 2,460 2,115
Interest Rate Swap [Member]    
Derivatives, Fair Value [Line Items]    
Derivative assets, current 0 0
Derivative Assets, Noncurrent 1 1
Total derivative assets 1 1
Current derivative liabilities 37 37
Derivative Liabilities, Noncurrent 61 53
Total derivative liabilities 98 90
Derivative, Fair Value, Net (97) (89)
Interest Rate Swap [Member] | Designated as Hedging Instrument [Member]    
Derivatives, Fair Value [Line Items]    
Total derivative assets 1 1
Total derivative liabilities 100 92
Interest Rate Swap [Member] | Not Designated as Hedging Instrument [Member]    
Derivatives, Fair Value [Line Items]    
Total derivative assets 0 0
Total derivative liabilities (2) (2)
Energy Related Derivative [Member]    
Derivatives, Fair Value [Line Items]    
Derivative assets, current 1,853 1,698
Derivative Assets, Noncurrent 419 312
Total derivative assets 2,272 2,010
Current derivative liabilities 1,938 1,697
Derivative Liabilities, Noncurrent 524 420
Total derivative liabilities 2,462 2,117
Derivative, Fair Value, Net (190) (107)
Energy Related Derivative [Member] | Not Designated as Hedging Instrument [Member]    
Derivatives, Fair Value [Line Items]    
Total derivative assets 2,272 2,010
Total derivative liabilities $ 2,462 $ 2,117