Share-Based Compensation (Details 1) $ / shares in Units, shares in Thousands, $ in Millions	12 Months Ended
	Sep. 30, 2017 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Outstanding shares, beginning balance | shares	5,098
Granted | shares	1,024
Exercised | shares	(2,168)
Forfeited | shares	(59)
Cancelled | shares	(6)
Outstanding shares, ending balance | shares	3,889
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest [Abstract]
Vested or expected to vest, shares | shares	2,642
Exercisable, shares | shares	1,847
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract]
Outstanding, beginning balance | $ / shares	$ 90.96
Granted | $ / shares	138.09
Exercised | $ / shares	81.70
Forfeited | $ / shares	122.45
Cancelled | $ / shares	65.54
Outstanding, ending balance | $ / shares	108.10
Vested or expected to vest | $ / shares	92.07
Exercisable | $ / shares	$ 92.14
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Outstanding, wtd. avg. remaining contractual term	7 years 2 months
Vested or expected to vest, wtd. avg. remaining contractual term	5 years 8 months
Exercisable, wtd. avg. remaining contractual term	5 years 7 months
Outstanding, Aggregate intrinsic value of in-the-money options | $	$ 272.6
Vested or expected, Aggregate intrinsic value of in-the-money options | $	227.6
Exercisable, Aggregate intrinsic value of in-the-money options | $	$ 158.9