Oil and Gas Assets (Tables)

9 Months Ended

Sep. 30, 2014

Oil and Gas Property [Abstract]

Costs incurred by year for oil and gas properties not subject to amortization

Oil and gas properties not subject to amortization as of September 30, 2014, consisted of the following:

	Costs Incurred In
	2014		2013		2012		2011 and Prior		Total
	(In millions)
Acquisition costs	$	129	$	199	$	86	$	410	$	824
Exploration costs	345		1		1		7		354
Development costs	14		8		31		11		64
Fee mineral interests	—		1		—		23		24
Capitalized interest	39		53		67		13		172
Total oil and gas properties not subject to amortization	$	527	$	262	$	185	$	464	$	1,438

Capitalized Costs Relating to Oil and Gas Producing Activities and Other PPE [Table Text Block]

Property and equipment consisted of the following:

	September 30,   2014			December 31,   2013
	(In millions)
Oil and gas properties:
Subject to amortization	$	14,348		$	15,107
Not subject to amortization	1,438			1,300
Gross oil and gas properties	15,786			16,407
Accumulated depreciation, depletion and amortization	(7,915		)	(8,306		)
Net oil and gas properties	$	7,871		$	8,101
Other property and equipment:
Furniture, fixtures and equipment	$	150		$	139
Gathering systems and equipment	111			104
Accumulated depreciation and amortization	(81		)	(69		)
Net other property and equipment	$	180		$	174