Business Segment Information (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Sales and operating results of reportable segments
Sales	$ 1,489.2	$ 1,473.9
Income before taxes	217.2	242.9
Total Segments [Member]
Sales and operating results of reportable segments
Income before taxes	276.0	291.9
Architecture and Software [Member]
Sales and operating results of reportable segments
Sales	657.5	650.5
Income before taxes	183.2	189.2
Control Products and Solutions [Member]
Sales and operating results of reportable segments
Sales	831.7	823.4
Income before taxes	92.8	102.7
Purchase accounting depreciation and amortization [Member]
Sales and operating results of reportable segments
Income before taxes	(5.2)	(5.0)
General corporate - net [Member]
Sales and operating results of reportable segments
Income before taxes	(18.5)	(20.2)
Non-operating pension cost [Member]
Sales and operating results of reportable segments
Income before taxes	(19.7)	(8.8)
Interest expense [Member]
Sales and operating results of reportable segments
Income before taxes	$ (15.4)	$ (15.0)