Financial Instruments (Cash, Cash Equivalents and Marketable Securities Fair Value Measurements) (Details) - USD ($) $ in Millions	Jul. 01, 2017	Dec. 31, 2016
Schedule of Investments [Line Items]
Cash, Cash Equivalents, and Marketable Securities, Fair Value Disclosure	$ 844	$ 1,264
Cash and Cash Equivalents, Fair Value Disclosure	760	1,264
Marketable Securities, Current, Fair Value Disclosure	84
Fair Value, Inputs, Level 1 [Member]
Schedule of Investments [Line Items]
Cash, Cash Equivalents, and Marketable Securities, Fair Value Disclosure	165	50
Cash and Cash Equivalents, Fair Value Disclosure	165	50
Marketable Securities, Current, Fair Value Disclosure	0
Fair Value, Inputs, Level 2 [Member]
Schedule of Investments [Line Items]
Cash, Cash Equivalents, and Marketable Securities, Fair Value Disclosure	589	1,147
Cash and Cash Equivalents, Fair Value Disclosure	505	1,147
Marketable Securities, Current, Fair Value Disclosure	84
Cash [Member]
Schedule of Investments [Line Items]
Cash, Cash Equivalents, and Marketable Securities, Fair Value Disclosure	90	67
Cash and Cash Equivalents, Fair Value Disclosure	90	67
Marketable Securities, Current, Fair Value Disclosure	0
Money Market Funds [Member]
Schedule of Investments [Line Items]
Cash, Cash Equivalents, and Marketable Securities, Fair Value Disclosure	165	50
Cash and Cash Equivalents, Fair Value Disclosure	165	50
Marketable Securities, Current, Fair Value Disclosure	0
Commercial Paper [Member] | Fair Value, Inputs, Level 2 [Member]
Schedule of Investments [Line Items]
Cash, Cash Equivalents, and Marketable Securities, Fair Value Disclosure	589	1,147
Cash and Cash Equivalents, Fair Value Disclosure	505	$ 1,147
Marketable Securities, Current, Fair Value Disclosure	$ 84