XML 84 R63.htm IDEA: XBRL DOCUMENT v2.4.0.8
Asset Impairments (Details) (USD $)
In Millions, unless otherwise specified
 3 Months Ended 9 Months Ended
Sep. 30, 2013
Sep. 30, 2013
Impaired Long-Lived Assets Held and Used [Line Items]    
Asset impairment charges, gross $ 7 $ 1,960
Asset impairment charges, net of taxes   1,343
U.S. Oil And Gas Assets [Member]
    
Impaired Long-Lived Assets Held and Used [Line Items]    
Asset impairment charges, gross   1,110
Asset impairment charges, net of taxes   707
Canada Oil And Gas Assets [Member]
    
Impaired Long-Lived Assets Held and Used [Line Items]    
Asset impairment charges, gross   843
Asset impairment charges, net of taxes   632
Midstream Assets [Member]
    
Impaired Long-Lived Assets Held and Used [Line Items]    
Asset impairment charges, gross   7
Asset impairment charges, net of taxes   $ 4