CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Operating Revenues:
Gas sales	$ 2,827	$ 2,381	$ 1,956
Oil sales	22	16	8
Marketing	996	792	592
Gas gathering	193	182	174
Total Operating Revenues	4,038	3,371	2,730
Operating Costs and Expenses:
Marketing purchases	980	782	592
Operating expenses	427	328	245
General and administrative expenses	221	191	175
Depreciation, depletion and amortization	942	787	811
Impairment of natural gas and oil properties			1,940
Taxes, other than income taxes	95	79	68
Total Operating Costs and Expenses	2,665	2,167	3,831
Operating Income (Loss)	1,373	1,204	(1,101)
Interest Expense:
Interest on debt	101	100	93
Other interest charges	13	4	4
Interest capitalized	(55)	(62)	(62)
Total Interest Expense	59	42	35
Other Income (Loss), Net	(4)	2	1
Gain (Loss) on Derivatives	139	26	(15)
Income (Loss) Before Income Taxes	1,449	1,190	(1,150)
Provision (Benefit) for Income Taxes:
Current	21	(11)	19
Deferred	504	497	(462)
Provision (benefit) for income taxes	525	486	(443)
Net Income (Loss)	$ 924	$ 704	$ (707)
Earnings (Loss) Per Share:
Basic	$ 2.63	$ 2.01	$ (2.03)
Diluted	$ 2.62	$ 2.00	$ (2.03)
Weighted Average Common Shares Outstanding:
Basic	351,446,747	350,465,430	348,610,503
Diluted	352,410,683	351,101,452	348,610,503