CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Cash Flows from Operating Activities
Net income (loss)	$ 2,445	$ (2,568)	$ 821
Adjustments to reconcile net income (loss) to net cash provided by operating activities
Depreciation, depletion, and amortization	3,964	3,830	3,714
Deferred income taxes	164	(1,461)	(123)
Dry hole expense and impairments of unproved properties	1,544	625	682
Impairments	389	1,774	216
(Gains) losses on divestitures, net	71	(22)	(29)
Unrealized (gains) losses on derivatives, net	377	616	(114)
Other	232	204	308
Changes in assets and liabilities
Deepwater Horizon settlement and related costs	24	(18)
Algeria exceptional profits tax settlement	(791)
Tronox-related contingent loss	(250)	250	(95)
(Increase) decrease in accounts receivable	520	(993)	(172)
Increase (decrease) in accounts payable and accrued expenses	(476)	284	(157)
Other items - net	126	(16)	196
Net cash provided by (used in) operating activities	8,339	2,505	5,247
Cash Flows from Investing Activities
Additions to properties and equipment and dry hole costs	(7,242)	(5,650)	(5,008)
Acquisition of midstream businesses		(802)
Divestitures of properties and equipment and other assets	657	555	70
Other - net	(284)	(78)	(26)
Net cash provided by (used in) investing activities	(6,869)	(5,975)	(4,964)
Cash Flows from Financing Activities
Borrowings, net of issuance costs	1,042	3,551	3,198
Repayments of debt	(3,044)	(1,154)	(1,879)
Repayment of midstream subsidiary note payable to a related party			(1,599)
Repayment of capital lease obligation		(108)
Increase (decrease) in accounts payable, banks	(69)	149	7
Dividends paid	(181)	(181)	(180)
Repurchase of common stock	(37)	(41)	(42)
Issuance of common stock, including tax benefit on stock option exercises	103	30	107
Sale of subsidiary units	623	328	338
Distributions to noncontrolling interest owners	(112)	(82)	(48)
Contributions from noncontrolling interest owners	16	17
Other financing activities		1	(24)
Net cash provided by (used in) financing activities	(1,659)	2,510	(122)
Effect of Exchange Rate Changes on Cash	(37)	(23)	(12)
Net Increase (Decrease) in Cash and Cash Equivalents	(226)	(983)	149
Cash and Cash Equivalents at Beginning of Period	2,697	3,680	3,531
Cash and Cash Equivalents at End of Period	$ 2,471	$ 2,697	$ 3,680