Summarized Financial Information of Equity Affiliates (Table of Summarized Financial Information of Equity Affiliates) (Details) - USD ($) $ in Millions	12 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017
Summarized Financial Information, Balance Sheet
Current assets	$ 1,660.6	$ 1,556.9
Noncurrent assets	4,400.4	4,340.8
Current liabilities	725.1	635.7
Noncurrent liabilities	2,853.6	2,652.5
Summarized Financial Information, Income Statement
Net sales	2,885.6	2,663.1	$ 2,343.3
Sales less cost of sales	1,193.4	1,050.6	878.6
Operating income	763.4	635.3	509.5
Net income	$ 492.4	$ 388.0	$ 343.5

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