Charges and Credits - Summary of Charges (Detail) - USD ($) $ in Millions	3 Months Ended				9 Months Ended
	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2015	Sep. 30, 2014
Investment In Joint Venture [Line Items]
Restructuring and other charges	$ 0	$ 0			$ 439	$ 0
Restructuring and other charges, tax					56
Restructuring and other charges, net					383
Workforce reduction
Investment In Joint Venture [Line Items]
Restructuring and other charges			$ 390		390
Restructuring and other charges, tax					56
Restructuring and other charges, net					334
Currency Devaluation Loss In Venezuela
Investment In Joint Venture [Line Items]
Restructuring and other charges			$ 49	$ 472	49
Restructuring and other charges, net					$ 49