Goodwill (Tables)

12 Months Ended

Dec. 31, 2013

Goodwill Disclosure [Abstract]

Schedule of Goodwill [Table Text Block]

The changes in the carrying amount of goodwill for 2012 were as follows for the Exploration and Production ("E&P") and OSM segments in place for that year:

(In millions)	E&P			OSM			Total
2012
Beginning balance, gross	$	536		$	1,412		$	1,948
Less: accumulated impairments	—			(1,412		)	(1,412		)
Beginning balance, net	536			—			536
Dispositions	(11		)	—			(11		)
Ending balance, net	$	525		$	—		$	525

As discussed in Note 8, beginning in 2013, we changed our reportable segments. Goodwill related to the previously reported E&P segment was allocated between the North America E&P and International E&P segments as of January 1, 2013 based on the relative fair values of those reporting units. The fair values of the reporting units were measured using an income approach based upon internal estimates of future production levels, commodity prices and discount rates, all of which are Level 3 inputs.  Inputs to the fair value measurements included reserve and production estimates made by our reservoir engineers, estimated commodity prices adjusted for quality and location differentials, and forecasted operating expenses. The table below displays the allocated beginning goodwill balances by segment along with changes in the carrying amount of goodwill for 2013:

(In millions)	N.A. E&P			Int'l E&P			OSM			Total
2013
Beginning balance, gross	$	343		$	182		$	1,412		$	1,937
Less: accumulated impairments	—			—			(1,412		)	(1,412		)
Beginning balance, net	343			182			—			525
Dispositions	4		(a)	(30		)	—			(26		)
Ending balance, net	$	347		$	152		$	—		$	499

^(a) Goodwill related to our Alaska disposition was less than the estimate classified as held for sale in 2012.