Asset Impairments (Tables)

6 Months Ended

Jun. 30, 2015

Asset Impairments [Abstract]

Summary of details of impairment of long-lived assets

Pre-tax (non-cash) asset impairment charges were as follows:

	Three Months Ended June 30,				Six Months Ended June 30,
(millions)	2015		2014		2015		2014
Deepwater Gulf of Mexico	$	8	$	18	$	11	$	23
Eastern Mediterranean	7		14		32		14
North Sea	—		2		—		94
Total	$	15	$	34	$	43	$	131