Software Development Costs and Intellectual Property Licenses (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013
Software development and intellectual property licenses:
Internally developed software costs	$ 211		$ 211		$ 189
Payments made to third-party software developers	248		248		199
Total software development costs	459		459		388
Intellectual property licenses	3		3		11
Amortization, write-offs and impairments:
Amortization of capitalized software development costs and intellectual property licenses	50	46	108	108
Write-offs and impairments	$ 0	$ 0	$ 0	$ 26