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	$ 2,645	$ 2,844	$ 1,842
Adjustments to reconcile net income to net cash flows from operating activities:
Depreciation, depletion, and amortization	1,628	1,359	1,119
Loss contingency for Macondo well incident	300	0	0
(Benefit) provision for deferred income taxes, continuing operations	165	(30)	124
(Income) loss from discontinued operations, net	(58)	166	(40)
Other changes:
Receivables	682	1,218	902
Inventories	(611)	(564)	(331)
Accounts payable	200	649	330
Other	67	478	70
Total cash flows from operating activities	3,654	3,684	2,212
Cash flows from investing activities:
Capital expenditures	(3,566)	(2,953)	(2,069)
Purchases of investment securities	(506)	(501)	(1,282)
Sales of property, plant, and equipment	395	160	227
Sales of investment securities	258	1,001	1,925
Acquisitions of business assets, net of cash acquired	(214)	(880)	(523)
Other investing activities	(55)	(17)	(33)
Total cash flows from investing activities	(3,688)	(3,190)	(1,755)
Cash flows from financing activities:
Dividends to shareholders	(333)	(330)	(327)
Proceeds from exercises of stock options	107	160	102
Payments to reacquire common stock	(33)	(43)	(141)
Proceeds from long-term borrowings, net of offering costs	0	978	0
Payments on long-term borrowings	0	0	(790)
Other financing activities	87	68	42
Total cash flows from financing activities	(172)	833	(1,114)
Effect of exchange rate changes on cash	(8)	(27)	(27)
Increase (decrease) in cash and equivalents	(214)	1,300	(684)
Cash and equivalents at beginning of year	2,698	1,398	2,082
Cash and equivalents at end of year	2,484	2,698	1,398
Cash payments during the period for:
Interest	294	261	310
Income taxes	$ 1,098	$ 1,285	$ 804