Accumulated Other Comprehensive Loss, Excluding Noncontrolling Interests (Detail) (USD $) In Millions, unless otherwise specified	9 Months Ended
	Sep. 30, 2012
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance, December 31, 2011	$ (4,129)
Other comprehensive income/(loss)	(1,524)	[1]
Balance, July 1, 2012	(5,653)
Net Unrealized Gain/(Losses) [Member] | Currency Translation Adjustment And Other [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance, December 31, 2011	944
Other comprehensive income/(loss)	(1,560)	[1]
Balance, July 1, 2012	(616)
Net Unrealized Gain/(Losses) [Member] | Derivative Financial Instruments [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance, December 31, 2011	(361)
Other comprehensive income/(loss)	76	[1]
Balance, July 1, 2012	(285)
Net Unrealized Gain/(Losses) [Member] | Available For-Sale Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance, December 31, 2011	46
Other comprehensive income/(loss)	126	[1]
Balance, July 1, 2012	172
Benefit Plans [Member] | Actuarial Gains/(Losses) [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance, December 31, 2011	(5,120)
Other comprehensive income/(loss)	(99)	[1]
Balance, July 1, 2012	(5,219)
Benefit Plans [Member] | Prior Service (Costs)/ Credits And Other [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance, December 31, 2011	362
Other comprehensive income/(loss)	(67)	[1]
Balance, July 1, 2012	$ 295

[1] Amounts do not include foreign currency translation adjustments attributable to noncontrolling interests of $19 million loss for the first nine months of 2012.