Business Segment Information (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Dec. 31, 2011	Dec. 31, 2010
Sales and operating results of reportable segments
Sales	$ 1,473.9	$ 1,365.8
Net income	183.3	150.1
Business Segment information (Textual) [Abstract]
Portion of total sales to largest distributor	10.00%	10.00%
Total Segments [Member]
Sales and operating results of reportable segments
Net income	283.8	222.0
Architecture and Software [Member]
Sales and operating results of reportable segments
Sales	650.5	613.9
Net income	186.3	153.1
Control Products and Solutions [Member]
Sales and operating results of reportable segments
Sales	823.4	751.9
Net income	97.5	68.9
Purchase accounting depreciation and amortization [Member]
Sales and operating results of reportable segments
Net income	(5.0)	(4.8)
General corporate - net [Member]
Sales and operating results of reportable segments
Net income	(20.9)	(15.7)
Interest expense [Member]
Sales and operating results of reportable segments
Net income	(15.0)	(14.8)
Income tax provision [Member]
Sales and operating results of reportable segments
Net income	$ (59.6)	$ (36.6)