Acquisitions, Goodwill, and Acquired Intangible Assets - Expected Future Amortization Expense of Acquired Intangible Assets (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013		Dec. 31, 2012
Business Combinations [Abstract]
2014	$ 157
2015	140
2016	121
2017	101
2018	54
Thereafter	72
Acquired Intangibles, Net	$ 645	[1]	$ 725	[1]

[1] Intangible assets have estimated useful lives of between one and 10 years.