Goodwill and Purchased Intangible Assets - Schedule of Goodwill (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2016
Goodwill [Roll Forward]
Goodwill, Gross	$ 2,756	$ 2,767
Accumulated Impairment Losses	(23)	(7)
Goodwill	2,733	2,760
Additions	9	2
Impairment		(16)
Other	(15)	(13)
Goodwill, Gross	2,750	2,756	$ 2,767
Accumulated Impairment Losses	(23)	(23)	(7)
Total	2,733	2,760	2,760	$ 2,727
Loss from disposal of IPS business	(6)	(34)	0
Software Segment [Domain]
Goodwill [Roll Forward]
Goodwill, Gross	1,936	1,947
Accumulated Impairment Losses	(7)	(7)
Goodwill	1,929	1,940
Additions	9	2
Impairment	0	0
Other	(15)	(13)
Goodwill, Gross	1,930	1,936	1,947
Accumulated Impairment Losses	(7)	(7)	(7)
Total	1,929	1,940	1,940	1,923
Services Segment [Domain]
Goodwill [Roll Forward]
Goodwill, Gross	658	658
Accumulated Impairment Losses	0	0
Goodwill	658	658
Additions	0	0
Impairment	0	0
Other	0	0
Goodwill, Gross	658	658	658
Accumulated Impairment Losses	0	0	0
Total	658	658	658	658
Hardware Segment [Domain]
Goodwill [Roll Forward]
Goodwill, Gross	162	162
Accumulated Impairment Losses	(16)	0
Goodwill	146	162
Additions	0	0
Impairment	0	(16)
Other	0	0
Goodwill, Gross	162	162	162
Accumulated Impairment Losses	(16)	(16)	0
Total	$ 146	162	$ 162	$ 146
Goodwill [Member]
Goodwill [Roll Forward]
Loss from disposal of IPS business		$ 16