Software Development and Intellectual Property Licenses (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Software development and intellectual property licenses:
Internally developed software costs	$ 266	$ 262
Payments made to third-party software developers	150	210
Total software development costs	416	472
Intellectual property licenses	30	23
Amortization, write-offs and impairments:
Amortization of capitalized software development costs and intellectual property licenses	410	272	$ 195
Write-offs and impairments	$ 4	$ 0	$ 29