Pension Plans, Other Postretirement Benefits, and Defined-Contribution Plans - Change in Benefit Obligation Table (Detail) (USD $)	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Pension Plans, Defined Benefit [Member]
Change in benefit obligation
Benefit obligation at beginning of year	$ 2,297,000,000	[1]	$ 2,024,000,000
Service cost	85,000,000		76,000,000		78,000,000
Interest cost	78,000,000		85,000,000		85,000,000
Actuarial (gain) loss	(156,000,000)		224,000,000
Participant contributions	0		1,000,000
Benefit payments	(149,000,000)		(117,000,000)
Foreign-currency exchange-rate changes	3,000,000		4,000,000
Benefit obligation at end of year (1)	2,158,000,000	[1]	2,297,000,000	[1]	2,024,000,000
Accumulated benefit obligation for all defined-benefit pension plans	1,800,000,000		2,100,000,000
Other Postretirement Benefit Plans, Defined Benefit [Member]
Change in benefit obligation
Benefit obligation at beginning of year	359,000,000		354,000,000
Service cost	9,000,000		9,000,000		9,000,000
Interest cost	14,000,000		16,000,000		16,000,000
Actuarial (gain) loss	(74,000,000)		(1,000,000)
Participant contributions	4,000,000		3,000,000
Benefit payments	(18,000,000)		(22,000,000)
Foreign-currency exchange-rate changes	0		0
Benefit obligation at end of year (1)	$ 294,000,000		$ 359,000,000		$ 354,000,000

[1] The accumulated benefit obligation for all defined-benefit pension plans was $1.8 billion at December 31, 2013, and $2.1 billion at December 31, 2012.