Accumulated Other Comprehensive Loss - Accumulated Other Comprehensive Loss (Detail) (USD $) In Millions, unless otherwise specified	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012
Accumulated Other Comprehensive Income Loss [Line Items]
Balance	$ (3,888)	$ (3,557)
Other comprehensive income (loss) before reclassifications	(131)	(25)
Amounts reclassified from accumulated other comprehensive loss	333	288
Income taxes	(40)	(31)
Net other comprehensive income (loss)	162	232
Balance	(3,726)	(3,325)
Currency Translation Adjustments
Accumulated Other Comprehensive Income Loss [Line Items]
Balance	(918)	(993)
Other comprehensive income (loss) before reclassifications	(139)	45
Amounts reclassified from accumulated other comprehensive loss
Income taxes
Net other comprehensive income (loss)	(139)	45
Balance	(1,057)	(948)
Fair Value of Derivatives
Accumulated Other Comprehensive Income Loss [Line Items]
Balance	30	(26)
Other comprehensive income (loss) before reclassifications	(27)	(35)
Amounts reclassified from accumulated other comprehensive loss	15	58
Income taxes
Net other comprehensive income (loss)	(12)	23
Balance	18	(3)
Pension and Other Postretirement Plans
Accumulated Other Comprehensive Income Loss [Line Items]
Balance	(3,141)	(2,538)
Other comprehensive income (loss) before reclassifications	(23)	(35)
Amounts reclassified from accumulated other comprehensive loss	318	230
Income taxes	(40)	(31)
Net other comprehensive income (loss)	255	164
Balance	(2,886)	(2,374)
Unrealized Gains Marketable Securities
Accumulated Other Comprehensive Income Loss [Line Items]
Balance	141
Other comprehensive income (loss) before reclassifications	58
Amounts reclassified from accumulated other comprehensive loss
Income taxes
Net other comprehensive income (loss)	58
Balance	$ 199