Consolidated Balance Sheets (USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Current assets:
Cash and cash equivalents	$ 383	$ 1,025
Accounts receivable:
Trade, net	341	436
Due from affiliates	2	4
Income taxes receivable	22	23
Inventories	266	241
Prepaid expenses	20	15
Other current assets:
Derivatives Assets, Current	624	578
Other	36	37
Total current assets	1,694	2,359
Oil and gas properties, using the successful efforts method of accounting:
Proved properties	16,005	15,662
Unproved properties	162	159
Accumulated depletion, depreciation and amortization	(5,727)	(5,431)
Total property, plant and equipment	10,440	10,390
Goodwill	272	272
Property, Plant and Equipment, Net	1,406	1,391
Other assets:
Investment in unconsolidated affiliate	259	239
Derivative Assets, Noncurrent	181	181
Other, net	95	94
Assets, Total	14,347	14,926
Accounts payable:
Trade	841	1,197
Due to affiliates	37	123
Interest payable	20	40
Income taxes payable	1	1
Deferred Tax Liabilities, Net, Current	185	161
Other current liabilities:
Derivative Liabilities, Current	16	3
Other	62	55
Total current liabilities	1,162	1,580
Long-term Debt, Excluding Current Maturities	2,668	2,665
Derivative Liabilities, Noncurrent	0	2
Deferred income taxes	1,738	1,803
Other liabilities	280	287
Stockholders' equity:
Common stock, $.01 par value	2	2
Additional paid-in capital	6,190	6,167
Treasury stock at cost	(201)	(171)
Retained earnings	2,500	2,583
Total equity attributable to common stockholders	8,491	8,581
Noncontrolling interests in consolidating subsidiaries	8	8
Total equity	8,499	8,589
Commitments and contingencies
Liabilities and Stockholders' Equity, Total	$ 14,347	$ 14,926