Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Numerator:
Net Income (Loss) Attributable to Parent	$ 474.8	$ 453.8	$ 1,113.2	$ 994.1
Denominator:
Denominator for basic earnings per share — weighted average common shares	372.3	377.4	373.5	376.6
Effect of dilutive securities:
Employee stock awards (shares)	4.6	6.0	4.7	7.0
Denominator for diluted earnings per share — adjusted weighted average common shares	376.9	383.4	378.2	383.6
Basic net income per common share attributable to Parent (in dollars per share)	$ 1.28	$ 1.20	$ 2.98	$ 2.64
Diluted net income per common share attributable to Parent (in dollars per share)	$ 1.26	$ 1.18	$ 2.94	$ 2.59