Acquisitions, Goodwill, and Acquired Intangible Assets Expected Future Amortization Expense of Acquired Intangible Assets (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013
Business Combinations [Abstract]
2015	$ 202
2016	185
2017	161
2018	106
2019	79
Thereafter	31
Acquired Intangibles, Net	$ 764	[1]	$ 645	[1]

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