Business Segment Information (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended								12 Months Ended
	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2011
Sales and operating results of reportable segments
Sales	$ 1,715.7	$ 1,624.2	$ 1,522.8	$ 1,489.2	$ 1,664.0	$ 1,560.4	$ 1,561.1	$ 1,473.9	$ 6,351.9	$ 6,259.4	$ 6,000.4
Income from continuing operations before income taxes	279.2	257.4	227.1	217.2	254.9	244.8	223.3	242.9	980.9	965.9	867.6
Purchase accounting depreciation and amortization									19.3	19.8	19.8
Interest expense									60.9	60.1	59.5
Operating Segments [Member]
Sales and operating results of reportable segments
Income from continuing operations before income taxes									1,236.8	1,163.9	1,048.8
Architecture and Software [Member]
Sales and operating results of reportable segments
Sales									2,682.0	2,650.4	2,594.3
Income from continuing operations before income taxes									759.4	714.4	670.4
Control Products and Solutions [Member]
Sales and operating results of reportable segments
Sales									3,669.9	3,609.0	3,406.1
Income from continuing operations before income taxes									477.4	449.5	378.4
Segment Reconciling Items [Member]
Sales and operating results of reportable segments
Purchase accounting depreciation and amortization									(19.3)	(19.8)	(19.8)
Non-operating pension cost									(78.5)	(35.2)	(23.5)
Corporate, Non-Segment [Member]
Sales and operating results of reportable segments
General corporate-net									(97.2)	(82.9)	(78.4)
Interest expense									$ (60.9)	$ (60.1)	$ (59.5)