Goodwill and Purchased Intangible Assets - Schedule of Goodwill (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2016	Dec. 31, 2015
Goodwill [Roll Forward]
Goodwill Gross	$ 2,759	$ 2,756
Accumulated Impairment Losses	(23)	(23)
Goodwill	2,733
Goodwill	2,736
Additions	9
Impairment	0
Other	(6)
Software Segment [Domain]
Goodwill [Roll Forward]
Goodwill Gross	1,939	1,936
Accumulated Impairment Losses	(7)	(7)
Goodwill	1,929
Goodwill	1,932
Additions	9
Other	(6)
Services Segment [Domain]
Goodwill [Roll Forward]
Goodwill Gross	658	658
Accumulated Impairment Losses	0	0
Goodwill	658
Goodwill	658
Additions	0
Other	0
Hardware Segment [Domain]
Goodwill [Roll Forward]
Goodwill Gross	162	162
Accumulated Impairment Losses	(16)	$ (16)
Goodwill	146
Goodwill	146
Additions	0
Other	$ 0