Business Segment Information (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2014	Mar. 31, 2013
Sales and operating results of reportable segments
Sales	$ 1,600.5	$ 1,522.8	$ 3,192.2	$ 3,012.0
Income before income taxes	248.4	227.1	521.2	444.3
Interest expense	(15.0)	(15.3)	(29.9)	(30.7)
Operating Segments [Member]
Sales and operating results of reportable segments
Income before income taxes	302.1	285.2	630.1	561.2
Architecture & Software [Member]
Sales and operating results of reportable segments
Sales	686.8	639.2	1,382.7	1,296.7
Income before income taxes	190.2	169.9	402.1	353.1
Control Products & Solutions [Member]
Sales and operating results of reportable segments
Sales	913.7	883.6	1,809.5	1,715.3
Income before income taxes	111.9	115.3	228.0	208.1
Segment Reconciling Items [Member]
Sales and operating results of reportable segments
Purchase accounting depreciation and amortization	(5.8)	(5.0)	(10.4)	(10.2)
Non-operating pension costs	(14.0)	(19.7)	(28.0)	(39.4)
Corporate, Non-Segment [Member]
Sales and operating results of reportable segments
General corporate - net	(18.9)	(18.1)	(40.6)	(36.6)
Interest expense	$ (15.0)	$ (15.3)	$ (29.9)	$ (30.7)