Business Acquisitions - Schedule of Recognized Identified Assets Acquired and Liabilities Assumed (Detail) (Arbitron, USD $) In Millions, unless otherwise specified	9 Months Ended
	Sep. 30, 2013
Arbitron
Business Acquisition [Line Items]
Business acquisition purchase price	$ 1,296
Accrued payment for directors’ and employees’ equity awards pertaining to pre-merger service	42
Accrued dividend payment on Arbitron common stock	3
Fair value of investment immediately before acquisition	75
Total	1,416
Identifiable assets acquired and liabilities assumed:
Cash	136
Other current assets	115
Property and equipment	32
Provisional allocation of purchase price to goodwill	931
Provisional allocation of purchase price to identified intangible assets	517
Other long term assets	3
Deferred revenue	(47)
Other current liabilities	(53)
Deferred tax liabilities	(200)
Other long term liabilities	(18)
Total	$ 1,416