Taxes (Details 2) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Changes to company's unrecognized tax benefits
Balance at January 1	$ 3,071		$ 3,481		$ 3,507
Foreign currency effects	(58)		4		(2)
Additions based on tax positions taken in current year	276		543		469
Additions/reductions resulting from current-year asset acquisitions/sales	0		0		(41)
Additions for tax positions taken in prior years	1,164		152		236
Reductions for tax positions taken in prior years	(176)		(899)		(366)
Settlements with taxing authorities in current year	(320)		(138)		(318)
Reductions as a result of a lapse of the applicable statute of limitations	(109)		(72)		(4)
Balance at December 31	3,848		3,071		3,481
Income Tax Authority [Line Items]
Excise and similar taxes on products and merchandise	8,492		8,010		8,085
Total taxes other than on income	13,063	[1]	12,376	[1]	15,628	[1]
United States
Income Tax Authority [Line Items]
Excise and similar taxes on products and merchandise	4,792		4,665		4,199
Import duties and other levies	4		1		4
Property and other miscellaneous taxes	1,036		782		726
Payroll taxes	255		240		236
Taxes on production	333		328		308
Total taxes other than on income	6,420		6,016		5,473
International
Income Tax Authority [Line Items]
Excise and similar taxes on products and merchandise	3,700		3,345		3,886
Import duties and other levies	41		106		3,511
Property and other miscellaneous taxes	2,486		2,501		2,354
Payroll taxes	168		160		148
Taxes on production	248		248		256
Total taxes other than on income	$ 6,643		$ 6,360		$ 10,155

[1] *Includes excise, value-added and similar taxes.$8,492 $8,010 $8,085See accompanying Notes to the Consolidated Financial Statements.