Summarized Financial Information of Equity Affiliates (Table of Summarized Financial Information of Equity Affiliates) (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019
Schedule of Equity Method Investments [Line Items]
Current assets	$ 8,376.3	$ 8,684.9
Noncurrent assets	18,482.9	16,483.6
Current liabilities	2,799.1	2,416.7
Noncurrent liabilities	9,972.1	10,308.7
Net sales	10,323.0	8,856.3	$ 8,918.9
Operating income	2,281.4	2,237.6	2,144.4
Net income	2,114.9	1,931.1	1,809.4
Equity Method Investment, Nonconsolidated Investee or Group of Investees
Schedule of Equity Method Investments [Line Items]
Current assets	2,244.6	1,943.5
Noncurrent assets	4,630.7	4,529.2
Current liabilities	774.0	765.3
Noncurrent liabilities	2,852.5	2,958.8
Net sales	3,338.1	2,809.1	2,885.6
Gross profit	1,492.9	1,212.5	1,193.4
Operating income	962.2	748.6	763.4
Net income	$ 646.0	$ 567.8	$ 492.4