Consolidated Statements of Cash Flows (unaudited) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Cash Flows From Operating Activities
Net Income (Loss)	$ (131)	$ 392
Adjustments to Reconcile Net Income to Net Cash Provided by Operating Activities
Depreciation, Depletion and Amortization	905	837
Asset Impairments	43	131
Dry Hole Cost	19	2
Deferred Income Tax (Benefit) Expense	(312)	24
Income (Loss) from Equity Method Investees, Net of Dividends	4	(3)
(Gain) Loss on Commodity Derivative Instruments	(63)	311
Net Cash Received (Paid) in Settlement of Commodity Derivative Instruments	397	(83)
Gain on Divestitures	(1)	(42)
Stock Based Compensation	38	45
Non-cash Pension Expense	21	0
Other Adjustments for Noncash Items Included in Income	12	38
Changes in Operating Assets and Liabilities
Decrease in Accounts Receivable	304	55
(Decrease) Increase in Accounts Payable	(167)	126
(Decrease) in Current Income Taxes Payable	(63)	(86)
Other Current Assets and Liabilities, Net	(45)	25
Other Operating Assets and Liabilities, Net	5	(15)
Net Cash Provided by Operating Activities	966	1,757
Cash Flows From Investing Activities
Additions to Property, Plant and Equipment	(1,898)	(2,321)
Additions to Equity Method Investments	(65)	(40)
Proceeds from Divestitures	151	146
Net Cash Used in Investing Activities	(1,812)	(2,215)
Cash Flows From Financing Activities
Exercise of Stock Options	4	41
Excess Tax Benefits from Stock-Based Awards	0	17
Dividends Paid, Common Stock	(134)	(116)
Purchase of Treasury Stock	(12)	(15)
Proceeds from Issuance of Shares of Common Stock to Public, Net of Offering Costs	1,112
Proceeds from Credit Facility, Net	0	600
Repayment of Senior Notes	0	(200)
Repayment of Capital Lease Obligation	(29)	(28)
Net Cash Provided by Financing Activities	941	299
Increase (Decrease) in Cash and Cash Equivalents	95	(159)
Cash and Cash Equivalents at Beginning of Period	1,183	1,117
Cash and Cash Equivalents at End of Period	$ 1,278	$ 958