XML 103 R86.htm IDEA: XBRL DOCUMENT v3.6.0.2
Derivatives and Financial Instruments (Summary of Commodity Derivative Assets and Liabilities) (Details) - Commodity derivatives - USD ($)
$ in Millions
Dec. 31, 2016
Dec. 31, 2015
Prepaid expenses and other current assets    
Fair value of commodity derivative assets and liabilities, without netting    
Assets $ 741 $ 2,607
Other assets    
Fair value of commodity derivative assets and liabilities, without netting    
Assets 5 5
Other accruals    
Fair value of commodity derivative assets and liabilities, without netting    
Liabilities 766 2,425
Other liabilities and deferred credits    
Fair value of commodity derivative assets and liabilities, without netting    
Liabilities $ 2 $ 5