Equity-Method Investments - Summarized Condensed Financial Information of LivingSocial (Detail) (LivingSocial, USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
LivingSocial
Statement of Operations:
Revenue	$ 399		$ 455		$ 238
Operating expense	461		666		613
Impairment charge	41		579		0
Operating loss from continuing operations	(103)		(790)		(375)
Net loss from continuing operations	(101)	[1]	(532)	[1]	(417)	[1]
Loss from discontinued operations, net of tax	(82)	[2]	(121)	[2]	(82)	[2]
Net loss	(183)		(653)		(499)
Balance Sheet:
Current assets	81		74
Non-current assets	152		216
Current liabilities	298		336
Non-current liabilities	36		14
Redeemable stock	$ 315		$ 205

[1] The difference between operating loss from continuing operations and net loss from continuing operations for 2012 is primarily due to non-operating, non-cash gains on previously held equity positions in companies that LivingSocial acquired during Q1 2012.

[2] In November 2013, LivingSocial announced that it had reached an agreement to sell its Korean operations for $260 million. The transaction closed in January 2014. The statement of operations information above has been recast to present its Korean operations as discontinued operations.