Changes in Balances of Accumulated Other Comprehensive Income by Component (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Equity And Accumulated Other Comprehensive Income [Line Items]
Balance at January 1, 2013			$ 2,235
Other comprehensive loss			(180)
Amounts reclassified to net income			(61)
Net other comprehensive loss	12	(195)	(136)	(91)
Net other comprehensive loss	(12)	(41)	(18)	(33)
Net other comprehensive loss	(26)	(10)	(15)	13
Net other comprehensive loss	(36)	(5)	(72)	(11)
Net other comprehensive loss	(62)	(251)	(241)	(122)
Balance at June 30, 2013	1,994		1,994
Foreign currency translation adjustments
Equity And Accumulated Other Comprehensive Income [Line Items]
Balance at January 1, 2013			793
Other comprehensive loss			(136)
Amounts reclassified to net income
Net other comprehensive loss			(136)
Balance at June 30, 2013	657		657
Unrealized loss on cash flow hedges
Equity And Accumulated Other Comprehensive Income [Line Items]
Balance at January 1, 2013			88
Other comprehensive loss			(37)
Amounts reclassified to net income			19
Net other comprehensive loss			(18)
Balance at June 30, 2013	70		70
Unrealized loss on marketable securities
Equity And Accumulated Other Comprehensive Income [Line Items]
Balance at January 1, 2013			101
Other comprehensive loss			(7)
Amounts reclassified to net income			(8)
Net other comprehensive loss			(15)
Balance at June 30, 2013	86		86
Defined benefit pension and postretirement plans
Equity And Accumulated Other Comprehensive Income [Line Items]
Balance at January 1, 2013			1,253
Amounts reclassified to net income			(72)
Net other comprehensive loss			(72)
Balance at June 30, 2013	$ 1,181		$ 1,181