Acquisitions, Goodwill, and Acquired Intangible Assets - Acquired Intangible Assets (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012
Acquired Finite-Lived Intangible Assets [Line Items]
Weighted Average Life Remaining	4 years 2 months 12 days	[1]
Acquired Intangibles, Gross	$ 1,248	[1],[2]	$ 1,162	[1],[2]
Accumulated Amortization	(603)	[1],[2]	(437)	[1],[2]
Acquired Intangibles, Net	645	[1]	725	[1]
Marketing-related
Acquired Finite-Lived Intangible Assets [Line Items]
Weighted Average Life Remaining	6 years 3 months 18 days
Acquired Intangibles, Gross	429	[2]	422	[2]
Accumulated Amortization	(156)	[2]	(113)	[2]
Acquired Intangibles, Net	273		309
Contract-based
Acquired Finite-Lived Intangible Assets [Line Items]
Weighted Average Life Remaining	3 years
Acquired Intangibles, Gross	173	[2]	177	[2]
Accumulated Amortization	(110)	[2]	(89)	[2]
Acquired Intangibles, Net	63		88
Technology and content- based
Acquired Finite-Lived Intangible Assets [Line Items]
Weighted Average Life Remaining	4 years 4 months 24 days
Acquired Intangibles, Gross	278	[2]	231	[2]
Accumulated Amortization	(74)	[2]	(30)	[2]
Acquired Intangibles, Net	204		201
Customer-related
Acquired Finite-Lived Intangible Assets [Line Items]
Weighted Average Life Remaining	2 years 4 months 24 days
Acquired Intangibles, Gross	368	[2]	332	[2]
Accumulated Amortization	(263)	[2]	(205)	[2]
Acquired Intangibles, Net	$ 105		$ 127

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

[2] Excludes the original cost and accumulated amortization of fully-amortized intangibles.