XML 42 R45.htm IDEA: XBRL DOCUMENT v3.3.0.814
Asset Retirement Obligation - Asset Retirement Obligation (Detail) - USD ($)
$ in Millions
9 Months Ended
Sep. 30, 2015
Dec. 31, 2014
Asset Retirement Obligation Disclosure [Abstract]    
Asset retirement obligation at beginning of year $ 3,085  
Liabilities incurred 54  
Liabilities divested (619)  
Liabilities settled (78)  
Accretion expense 122  
Revisions in estimated liabilities 31  
Asset retirement obligation at end of year 2,595  
Less current portion (28) $ (37)
Asset retirement obligation, long-term $ 2,567 $ 3,048