Intangible Assets - Changes in Carrying Amount of Goodwill and Intangible Assets (Detail) (USD $) In Millions, unless otherwise specified	1 Months Ended	6 Months Ended
	May 31, 2014	Jun. 30, 2014	Jun. 30, 2013
Non-Amortizable Assets:
Goodwill, Beginning Balance		$ 986	$ 986
Goodwill, Additions	14	14
Goodwill, Ending Balance		1,000	986
Trademarks and tradenames, Beginning Balance		314	314
Trademarks and tradenames, Additions		0
Trademarks and tradenames, Ending Balance		314	314
Other Intangible Assets:
Other intangible assets, net, Beginning Balance		671	717
Other intangible assets, net, Additions		(4)	(33)
Other intangible assets, net, Foreign Exchange		2	(3)
Other intangible assets, net, Ending Balance		669	681
Acquired Intangible Assets [Member]
Other Intangible Assets:
Total other intangible assets, Beginning Balance		1,129	1,129
Total other intangible assets, Additions		0
Total other intangible assets, Foreign Exchange		1
Total other intangible assets, Ending Balance		1,130	1,129
Accumulated amortization, Beginning Balance		(610)	(530)
Accumulated amortization, Additions		(39)	(40)
Accumulated amortization, Ending Balance		(649)	(570)
Other intangible assets, net, Beginning Balance		519	599
Other intangible assets, net, Additions		(39)	(40)
Other intangible assets, net, Foreign Exchange		1
Other intangible assets, net, Ending Balance		481	559
Customer Loyalty Payments [Member]
Other Intangible Assets:
Total other intangible assets, Beginning Balance		306	274
Total other intangible assets, Additions		72	36
Total other intangible assets, Retirements		(44)	(50)
Total other intangible assets, Foreign Exchange		1	(3)
Total other intangible assets, Ending Balance		335	257
Accumulated amortization, Beginning Balance		(154)	(156)
Accumulated amortization, Additions		(37)	(29)
Accumulated amortization, Retirements		44	50
Accumulated amortization, Foreign Exchange		0
Accumulated amortization, Ending Balance		(147)	(135)
Other intangible assets, net, Beginning Balance		152	118
Other intangible assets, net, Additions		35	7
Other intangible assets, net, Foreign Exchange		1	(3)
Other intangible assets, net, Ending Balance		$ 188	$ 122