Basis of Presentation (Details) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended				9 Months Ended
	Sep. 30, 2012		Sep. 30, 2011		Sep. 30, 2012		Sep. 30, 2011		Dec. 31, 2011
Other Revenues [Abstract]
Other Revenues	$ 1		$ 0		$ 0		$ 33	[1]
Production Expense
Lease Operating Expense	103		89		309		251
Production and Ad Valorem Taxes	31		38		112		108
Transportation and Gathering Expense	24		15		71		47
Total	158		142		492		406
Other Operating (Income) Expense, Net
Deepwater Gulf of Mexico Moratorium Expense	0	[2]	(1)	[2]	0	[2]	18	[2]
Electricity Generation Expense	0		0		0		26	[1]
Other, Net	(1)		3		19		1
Total	(1)		2		19		45
Other Non-Operating (Income) Expense, Net
Deferred Compensation (Income) Expense	7	[3]	(18)	[3]	(1)	[3]	(15)	[3]
Interest Income	(1)		(2)		(1)		(7)
Other (Income) Expense, Net	(2)		4		4		6
Total	4		(16)		2		(16)
Accounts Receivable, Net
Commodity Sales	264				264				356
Joint Interest Billings	295				295				313
Other	136				136				123
Allowance for Doubtful Accounts	(9)				(9)				(9)
Total	686				686				783
Other Current Assets
Inventories, Current	88				88				78
Commodity Derivative Assets	35				35				10
Deferred Income Taxes, Net	104	[4]			104	[4]			41	[4]
Probable Insurance Claims	39	[5]			39	[5]			15	[5]
Assets Held-for-Sale	73	[6]			73	[6]			0
Prepaid Expense and Other Current Assets	83				83				36
Total	422				422				180
Other Noncurrent Assets
Equity Method Investments	363				363				329
Mutual Fund Investments	110				110				99
Commodity Derivative Assets	24				24				37
Other Assets, Noncurrent	128				128				83
Total	625				625				548
Other Current Liabilities
Production and Ad Valorem Taxes	117				117				121
Commodity Derivative Liabilities	16				16				76
Income Taxes Payable	209				209				127
Asset Retirement Obligations	41				41				33
Interest Payable	40				40				56
CONSOL Installment Payment	322	[7]			322	[7]			324	[7]
Current Portion of FPSO Lease Obligation	48				48				45
Liabilities Associated with Assets Held for Sale	34	[6]			34	[6]			0
Other	187				187				143
Total	1,014				1,014				925
Other Noncurrent Liabilities
Deferred Compensation Liabilities	237				237				222
Asset Retirement Obligations	279				279				344
Accrued Benefit Costs	88				88				88
Commodity Derivative Liabilities	5				5				7
Other	82				82				91
Total	$ 691				$ 691				$ 752
Common stock, shares authorized (in shares)	500,000,000				500,000,000				250,000,000
Common stock, par value per share (in dollars per share)	$ 0.01				$ 0.01				$ 3.333

[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.

[2] Amounts relate to rig stand-by expense incurred prior to receiving a permit to resume drilling activities in the deepwater Gulf of Mexico.

[3] Amounts represent increases (decreases) in the fair value of shares of our common stock held in a rabbi trust.

[4] Increase from December 31, 2011 is due to reclassification of deferred income tax assets from long-term to short-term as certain foreign entities are estimated to begin utilizing net operating loss carryforwards in 2012 and 2013.

[5] Amounts represent the costs incurred to date of the Leviathan-2 appraisal well and expected well abandonment costs in excess of the insurance deductible less insurance proceeds received to date. See Note 9. Asset Retirement Obligations.

[6] Assets held for sale consists primarily of oil and gas properties and liabilities held for sale consists primarily of asset retirement obligations.

[7] See Note 3. Acquisitions and Dispositions and Note 5. Debt.