Acquisitions and Divestitures (Details 2) (USD $) In Millions, unless otherwise specified	9 Months Ended	12 Months Ended	1 Months Ended	12 Months Ended	5 Months Ended	12 Months Ended	1 Months Ended	9 Months Ended	12 Months Ended				1 Months Ended	7 Months Ended	12 Months Ended		5 Months Ended	12 Months Ended		1 Months Ended
	Dec. 31, 2012	Dec. 31, 2013	Sep. 30, 2013 Four Star	Dec. 31, 2013 Four Star	May 24, 2012 Predecessor	Dec. 31, 2011 Predecessor	Jun. 30, 2013 CBM properties, natural gas properties in South Texas and majority of Arklatex along with Brazil operations natural gas properties item	Dec. 31, 2012 CBM properties, natural gas properties in South Texas and majority of Arklatex along with Brazil operations natural gas properties	Dec. 31, 2013 CBM properties, natural gas properties in South Texas and majority of Arklatex along with Brazil operations natural gas properties	Dec. 31, 2013 Domestic oil and natural gas properties	Dec. 31, 2012 Oil and natural gas properties located in the Gulf of Mexico	Dec. 31, 2012 Unevaluated property interests in Egypt	Jun. 30, 2013 Brazil operations	Dec. 31, 2013 Brazil operations	Dec. 31, 2013 Brazil operations	Dec. 31, 2012 Brazil operations	May 24, 2012 Brazil operations Predecessor	Dec. 31, 2011 Brazil operations Predecessor	Dec. 31, 2011 Non-core oil and natural gas properties Predecessor	Feb. 28, 2014 Domestic natural gas assets in Atklatex area Subsequent event
Divestitures
Number of sale agreements							3
Proceeds from sale of assets	$ 110	$ 1,451			$ 9	$ 612			$ 1,300	$ 10		$ 22							$ 612	$ 16
Gain on sale of assets		468							468											12
Equity interest percentage sold				49.00%
Net proceeds from the sale of investments			183	183
Impairment in earnings from unconsolidated affiliates			20	20
Impairment charges	1	2			62	6							10	24	34
Proceeds from sale of oil and gas properties net of purchase price adjustments											79
Summary of operating results and financial position data of discontinued operations
Operating revenues								262	297								46	111
Operating expenses
Natural gas purchases								23	19
Transportation costs								22	18
Lease operating expense								65	76								16	40
Depreciation, depletion and amortization								59	48								12	33
Impairment and ceiling test charges									44									152
Other expense								50	41								20	31
Total operating expenses								219	246								48	256
Gain on sale of assets		468							468											12
Other (expense) income								3	(2)								(5)	(1)
Income (loss) from discontinued operations before income taxes								46	517								(7)	(146)
Income tax expense (benefit)								2	7								2	(23)
Income (loss) from discontinued operations, net of tax	44	510			(9)	(123)		44	510								(9)	(123)
Assets of discontinued operations
Current assets	1,034	88						95	26
Property, plant and equipment, net								1,019	52
Other non-current assets								13	10
Total assets of discontinued operations								1,127	88
Liabilities of discontinued operations
Accounts payable								84	39
Other current liabilities								16	10
Asset retirement obligations								146	37					37	37	36
Other non-current liabilities								7	5
Total liabilities of discontinued operations								$ 253	$ 91