Information Relating to the Consolidated Statement of Cash Flows (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Net (increase) decrease in operating working capital
Increase in accounts and notes receivable	$ (994)	$ (153)
Increase in inventories	(520)	(1,847)
Increase in prepaid expenses and other current assets	(437)	(119)
Decrease in accounts payable and accrued liabilities	(1,759)	(1,027)
Increase in income and other taxes payable	350	351
Net (increase) decrease in operating working capital	(3,360)	(2,795)
Cash Payment for Interest on Debt and For Income Taxes
Interest on debt (net of capitalized interest)	0	36
Income taxes	3,434	4,140
Net (purchases) sales of time deposits
Time deposits purchased	(708)	(8)
Time deposits matured	8	3,308
Net (purchases) sales of time deposits	(700)	3,300
Net sales of marketable securities
Marketable securities purchased	0	0
Marketable securities sold	0	11
Net sales of marketable securities	0	11
Capital expenditures
Additions to properties, plant and equipment	7,935	5,511
Additions to investments	262	192
Current year dry hole expenditures	12	205
Payments for other liabilities and assets, net	(17)	(13)
Capital expenditures	8,192	5,895
Expensed exploration expenditures	235	161
Assets acquired through capital lease obligations	2	0
Capital and exploratory expenditures, excluding equity affiliates	8,429	6,056
Company's share of expenditures by equity affiliates	453	361
Capital and exploratory expenditures, including equity affiliates	$ 8,882	$ 6,417