Consolidated Statements of Total Equity - USD ($) $ in Millions	Total	Common Stock	Additional Paid-in Capital	Retained Earnings	Treasury Stock	Accumulated Other Comprehensive Income	Non-controlling Interests
Beginning Balances at Sep. 30, 2015	$ 5,895.4	$ 3.8	$ 2,733.8	$ 3,289.6	$ (134.3)	$ 1.4	$ 1.1
Increase (Decrease) in Stockholders' Equity
Net income	886.3			886.3			0.0
Issuances under employee benefit plans	2.2		2.2
Exercise of stock options	70.1		70.1
Tax benefit from employee stock awards	2.7	0.0	2.7	0.0	0.0	0.0	0.0
Stock issued under employee incentive plans	13.9		13.9
Cash paid for shares withheld for taxes	(5.9)	0.0	(5.9)	0.0	0.0	0.0	0.0
Stock based compensation expense	49.0		49.0
Cash dividends declared	(118.7)			(118.7)
Other comprehensive income, net of tax	(1.4)					(1.4)
Noncontrolling interests	(0.6)						(0.6)
Ending Balances at Sep. 30, 2016	6,793.0	3.8	2,865.8	4,057.2	(134.3)	0.0	0.5
Increase (Decrease) in Stockholders' Equity
Net income	1,038.4			1,038.4			0.0
Issuances under employee benefit plans	2.8		2.8
Exercise of stock options	43.8		43.8
Tax benefit from employee stock awards	13.7	0.0	13.7	0.0	0.0	0.0	0.0
Stock issued under employee incentive plans	12.0		12.0
Cash paid for shares withheld for taxes	(5.1)	0.0	(5.1)	0.0	0.0	0.0	0.0
Stock based compensation expense	59.2		59.2
Cash dividends declared	(149.6)			(149.6)
Repurchases of common stock	(60.6)				(60.6)
Ending Balances at Sep. 30, 2017	7,747.6	3.8	2,992.2	4,946.0	(194.9)	0.0	0.5
Increase (Decrease) in Stockholders' Equity
Noncontrolling interests acquired	175.2						175.2
Net income	1,462.3			1,460.3			2.0
Issuances under employee benefit plans	4.0		4.0
Exercise of stock options	43.4	0.1	43.3
Stock issued under employee incentive plans			0.0
Cash paid for shares withheld for taxes	(10.3)	0.0	(10.3)	0.0	0.0	0.0	0.0
Stock based compensation expense	55.8		55.8
Cash dividends declared	(188.4)			(188.4)
Repurchases of common stock	(127.5)				(127.5)
Distributions to noncontrolling interests	(3.2)						(3.2)
Ending Balances at Sep. 30, 2018	$ 9,158.9	$ 3.9	$ 3,085.0	$ 6,217.9	$ (322.4)	$ 0.0	$ 174.5