Business Combinations Intangibles (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 28, 2018	Aug. 17, 2018
Intangible Assets Excluding Goodwill [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles		$ 48.0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Indefinite-Lived Intangible Assets		94.0
Developed Technology and Other [Member]
Intangible Assets Excluding Goodwill [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	2 years
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles		37.3
Customer-Related Intangible Assets [Member]
Intangible Assets Excluding Goodwill [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	1 year
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles		10.4
Trade Names [Member]
Intangible Assets Excluding Goodwill [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles		0.3
In Process Research and Development [Member]
Intangible Assets Excluding Goodwill [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Indefinite-Lived Intangible Assets		$ 46.0