Condensed Consolidated Statements of Cash Flows (Unaudited) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Cash flows from operating activities:
Net income (loss)	$ (16)	$ 630
Adjustments to reconcile net income to net cash flows from operating activities:
Loss contingency for Macondo well incident	1,000	300
Depreciation, depletion, and amortization	448	385
Other changes:
Receivables	(406)	(233)
Payment related to KBR separation	(219)	0
Accounts payable	158	104
Inventories	(70)	(346)
Other	546	106
Total cash flows from operating activities	349	734
Cash flows from investing activities:
Capital expenditures	(685)	(782)
Purchases of investment securities	(28)	(100)
Sales of investment securities	9	150
Other investing activities	53	5
Total cash flows from investing activities	(651)	(727)
Cash flows from financing activities:
Dividends to shareholders	(116)	(83)
Other financing activities	(29)	34
Total cash flows from financing activities	(145)	(49)
Effect of exchange rate changes on cash	(8)	(1)
Increase (decrease) in cash and equivalents	(455)	(43)
Cash and equivalents at beginning of period	2,484	2,698
Cash and equivalents at end of period	2,029	2,655
Cash payments during the period for:
Interest	123	122
Income taxes	$ 137	$ 165