Basis of Presentation (Recent Accounting Pronouncements) (Details) - USD ($) $ in Millions	6 Months Ended
	Jul. 02, 2016	Jul. 04, 2015	Dec. 31, 2015
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net cash provided by operating activities from continuing operations	$ 304	$ 306
Net cash provided by (used for) financing activities from continuing operations	(51)	(1,051)
Accounting Standards Update 2016-09 | New Accounting Pronouncement, Early Adoption, Effect
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Income tax benefit impact of adoption	3
Accounting Standards Update 2016-09, Excess Tax Benefit Component | New Accounting Pronouncement, Early Adoption, Effect
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net cash provided by operating activities from continuing operations	3
Net cash provided by (used for) financing activities from continuing operations	(3)
Accounting Standards Update 2016-09, Statutory Tax Withholding Component | New Accounting Pronouncement, Early Adoption, Effect
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net cash provided by operating activities from continuing operations	14	14
Net cash provided by (used for) financing activities from continuing operations	(14)	$ (14)
Long-term Debt | Accounting Standards Update 2015-03
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Debt issuance costs presented as a component of long-term debt	$ 35		$ 41