Stockholders' Equity and Noncontrolling Interests - Repurchase table (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Sep. 28, 2018	Sep. 29, 2017	Sep. 30, 2016
Accelerated Share Repurchases [Line Items]
Number (in shares)	1.6	3.3	5.7
Average repurchase price ($ per share)	$ 112.63	$ 90.63	$ 81.61
Total cost	$ 181.9	$ 294.5	$ 461.3
Accelerated Share Repurchase Program
Accelerated Share Repurchases [Line Items]
Number (in shares)			1.0
Average repurchase price ($ per share)			$ 83.98
Total cost			$ 85.8