Consolidated Statements of Operations (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011		Dec. 31, 2010
Revenues
Oil, Gas and NGL Sales	$ 4,037	$ 3,179		$ 2,523
Income from Equity Method Investees	186	193		118
Other Revenues	0	32	[1]	72	[1]
Total Revenues	4,223	3,404		2,713
Costs and Expenses
Production Expense	673	558		515
Exploration Expense	409	277		242
Depreciation, Depletion and Amortization	1,370	878		819
General and Administrative	384	339		273
Gain on Divestitures	(154)	(25)		(113)
Asset Impairments	104	757		144
Other Operating (Income) Expense, Net	25	86		64
Total Operating Expenses	2,811	2,870		1,944
Operating Income	1,412	534		769
Other (Income) Expense
Gain on Commodity Derivative Instruments	(75)	(42)		(157)
Interest, Net of Amount Capitalized	125	65		72
Other Non-Operating (Income) Expense, Net	6	9		6
Total Other (Income) Expense	56	32		(79)
Total	1,356	502		848
Income Tax Provision	391	90		217
Income from Continuing Operations	965	412		631
Discontinued Operations, Net of Tax	62	41		94
Net Income	$ 1,027	$ 453		$ 725
Earnings Per Share, Basic
Income from Continuing Operations (in dollars per share)	$ 5.43	$ 2.34		$ 3.61
Discontinued Operations, Net of Tax (in dollars per share)	$ 0.34	$ 0.23		$ 0.54
Net Income (in dollars per share)	$ 5.77	$ 2.57		$ 4.15
Earnings Per Share, Diluted
Income from Continuing Operations (in dollars per share)	$ 5.37	$ 2.31		$ 3.56
Discontinued Operations, Net of Tax (in dollars per share)	$ 0.34	$ 0.23		$ 0.54
Net Income (in dollars per share)	$ 5.71	$ 2.54		$ 4.10
Weighted Average Number of Shares Outstanding, Basic (in shares)	178	176		175
Weighted Average Number of Shares Outstanding, Diluted (in shares)	180	179		177

[1] Other revenues consist primarily of electricity sales from the Machala power plant, located in Machala, Ecuador, through May 2011. Electricity generation expense includes all operating and non-operating expenses associated with the plant, including depreciation and changes in the allowance for doubtful accounts. In May 2011, we transferred our assets in Ecuador to the Ecuadorian government.