Employee Pension and Other Benefit Plans - Employee Pension and Other Benefit Plans (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Pension Benefit Costs [Member]
Employee Related Benefits [Line Items]
Service cost	$ 6	$ 9
Interest cost	10	10
Expected return on plan assets	(13)	(12)
Amortization, net	3	8
Benefit costs, net	6	15
Other Benefit Costs [Member]
Employee Related Benefits [Line Items]
Service cost	1	1
Interest cost	2	1
Benefit costs, net	$ 3	$ 2