Software Development Costs and Intellectual Property Licenses (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Software development and intellectual property licenses:
Internally developed software costs	$ 159	$ 115
Payments made to third-party software developers	134	84
Total software development costs	293	199
Intellectual property licenses	41	34
Amortization, write-offs and impairments:
Amortization of capitalized software development costs and intellectual property licenses	205	258	322
Write-offs and impairments	$ 12	$ 60	$ 63