Other Financial Data - Schedule of Other Current Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Other Financial Data [Abstract]
Deferred revenue	$ 394	$ 408
Taxes payable	94	64
Deferred tax liability	1	2
Other	331	314
Total Other Current Liabilities	$ 820	$ 788