Accumulated Other Comprehensive Loss - Schedule of Accumulated Other Comprehensive Loss (Detail) (USD $) In Millions, unless otherwise specified	9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013
Accumulated Other Comprehensive Income Loss [Line Items]
Balance	$ (2,554)	$ (3,888)
Other comprehensive income (loss) before reclassifications	(446)	(131)
Amounts reclassified from accumulated other comprehensive loss	287	333
Income taxes	(28)	(40)
Net other comprehensive income (loss)	(187)	162
Balance	(2,741)	(3,726)
Currency Translation Adjustments
Accumulated Other Comprehensive Income Loss [Line Items]
Balance	(1,068)	(918)
Other comprehensive income (loss) before reclassifications	(176)	(139)
Net other comprehensive income (loss)	(176)	(139)
Balance	(1,244)	(1,057)
Fair Value of Derivatives
Accumulated Other Comprehensive Income Loss [Line Items]
Balance	29	30
Other comprehensive income (loss) before reclassifications	(138)	(27)
Amounts reclassified from accumulated other comprehensive loss	59	15
Net other comprehensive income (loss)	(79)	(12)
Balance	(50)	18
Pension and Other Postretirement Benefit Plans
Accumulated Other Comprehensive Income Loss [Line Items]
Balance	(1,691)	(3,141)
Other comprehensive income (loss) before reclassifications		(23)
Amounts reclassified from accumulated other comprehensive loss	228	318
Income taxes	(28)	(40)
Net other comprehensive income (loss)	200	255
Balance	(1,491)	(2,886)
Unrealized Gains on Marketable Securities
Accumulated Other Comprehensive Income Loss [Line Items]
Balance	176	141
Other comprehensive income (loss) before reclassifications	(132)	58
Net other comprehensive income (loss)	(132)	58
Balance	$ 44	$ 199