Accumulated Other Comprehensive Income/(Loss) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Dec. 31, 2011
Foreign currency transaction
Other comprehensive income/(loss), net of tax	$ 440	$ (1,317)	$ 185	$ (481)
Derivative instruments
Other comprehensive income/(loss), net of tax	1	43	(151)	177
Pension and other postretirement benefits
Other comprehensive income/(loss), net of tax	(54)	241	159	346
Net holding gain/(loss)
Total AOCI ending balance	(18,541)		(18,541)		(18,734)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Noncontrolling Interest [Abstract]
Foreign currency transaction losses attributable to noncontrolling interests				2
Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Tax, Portion Attributable to Parent [Abstract]
Net gain/(loss) on foreign currency translation, tax			0	0
Reclassifications to net income, tax			0	0
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Tax, Portion Attributable to Parent [Abstract]
Net gain/(loss) on derivative instruments, tax			(153)	21
Reclassifications to net income, tax			83	(25)
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Tax, Portion Attributable to Parent [Abstract]
Prior service cost arising during the period, tax			0	0
Net gain/(loss) arising during the period, tax			0	0
Amortization of prior service cost included in net income, tax			(84)	7
Amortization of gain/(loss) included in net income, tax			225	26
Translation Impact on non-U.S. plans, tax			0	0
Other Comprehensive Income (Loss), Available-for-sale Securities, Tax, Portion Attributable to Parent [Abstract]
Reclassifications to net income, tax			0	0
Parent [Member]
Foreign currency transaction
Beginning balance			(1,383)	(665)
Net gain/(loss) on foreign currency translation			185	(471)
Reclassifications to net income			0	(8)
Other comprehensive income/(loss), net of tax			185	(479)
Ending balance	(1,198)	(1,144)	(1,198)	(1,144)
Derivative instruments
Beginning balance			(181)	(29)
Net gain/(loss) on derivative instruments			(347)	233
Reclassifications to net income			196	(56)
Other comprehensive income/(loss), net of tax			(151)	177
Ending balance	(332)	148	(332)	148
Pension and other postretirement benefits
Beginning balance			(17,170)	(13,617)
Prior service cost arising during the period			0	(45)
Net gain/(loss) arising during the period			0	(57)
Amortization of prior service cost included in net income			(116)	(173)
Amortization of (gain)/loss included in net income			498	536
Translation impact on non-U.S. plans			(223)	85
Other comprehensive income/(loss), net of tax			159	346
Ending balance	(17,011)	(13,271)	(17,011)	(13,271)
Net holding gain/(loss)
Beginning balance			0	(2)
Reclassifications to net income			0	0
Ending balance	0	(2)	0	(2)
Total AOCI ending balance	$ (18,541)	$ (14,269)	$ (18,541)	$ (14,269)