Restructuring Expenses (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Apr. 01, 2016
Restructuring Reserve [Roll Forward]
Restructuring expenses	$ 13	$ 0
Restructuring Due To IS&GS Acquisition
Restructuring Reserve [Roll Forward]
Restructuring reserve, opening balance	8
Restructuring expenses	13
Cash payments	(17)
Restructuring reserve, closing balance	$ 4
Period to settle restructuring liability, minimum (in years)	1 year
Restructuring Due To IS&GS Acquisition | Severance costs
Restructuring Reserve [Roll Forward]
Restructuring reserve, opening balance	$ 7
Restructuring expenses	10
Cash payments	(14)
Restructuring reserve, closing balance	3
Restructuring Due To IS&GS Acquisition | Lease termination expenses
Restructuring Reserve [Roll Forward]
Restructuring reserve, opening balance	1
Restructuring expenses	3
Cash payments	(3)
Restructuring reserve, closing balance	$ 1