Impairment and Exploration Expenses (Tables)

12 Months Ended

Dec. 31, 2015

Impairments and Exploration Expenses [Abstract]

Details of Impairment of Long-Lived Assets Held and Used by Asset [Table Text Block]

The following table summarizes impairment charges of proved properties:

	Year Ended December 31,
(in millions)	2015		2014		2013
Total impairments	$	752	$	132	$	96

Exploration Expenses [Table Text Block]

The following table summarizes the components of exploration expenses:

	Year Ended December 31,
(In millions)	2015		2014		2013
Exploration Expenses
Unproved property impairments	$	964	$	306	$	572
Dry well costs	250		317		148
Geological and geophysical	31		85		80
Other	73		85		91
Total exploration expenses	$	1,318	$	793	$	891