Stockholders' Equity and Noncontrolling Interests - Repurchase table (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Sep. 29, 2017	Sep. 30, 2016	Oct. 02, 2015
Accelerated Share Repurchases [Line Items]
Number (in shares)	3.3	5.7	4.8
Average repurchase price ($ per share)	$ 90.63	$ 81.61	$ 87.47
Total cost	$ 294.5	$ 461.3	$ 422.0
Accelerated Share Repurchase Program
Accelerated Share Repurchases [Line Items]
Number (in shares)		1.0	2.3
Average repurchase price ($ per share)		$ 83.98	$ 90.00
Total cost		$ 85.8	$ 203.9