Investments (Narrative) (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2018	Jul. 01, 2017
Investments [Abstract]
Proceeds from Sale of Available-for-sale Securities	$ 45	$ 20
Subsequent Event, Date	Jul. 27, 2018
Subsequent Event, Description	we acquired a minority interest in Essence Group Holdings Corporation ("Essence Group") for cash consideration of $266 million under a Stock Purchase Agreement ("SPA") dated July 9, 2018.