Fair Value Measurements and Fair Value of Financial Instruments Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation (Details) - Contingent Consideration [Member] - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Apr. 01, 2017
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance	$ 35	$ 6
Acquisitions	11	9
Payments	(5)
Change in fair value included in earnings		25
Ending Balance	$ 41	$ 40