Summarized Financial Information of Equity Affiliates (Table of Summarized Financial Information of Equity Affiliates) (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2015
Summarized Financial Information, Balance Sheet
Current assets	$ 1,333.2	$ 1,436.7
Noncurrent assets	4,026.9	3,063.3
Current liabilities	666.8	694.8
Noncurrent liabilities	2,194.3	1,540.4
Summarized Financial Information, Income Statement
Net sales	2,343.3	2,271.6	$ 2,460.5
Sales less cost of sales	878.6	871.5	922.7
Operating income	509.5	482.1	512.4
Net income	$ 343.5	$ 334.1	$ 343.5