Business Segment Information (Reconciliation of Segment Operating Income to Consolidated Results) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Segment Reporting [Line Items]
Operating income (loss)	$ (2,097.1)	$ 790.6	$ (609.9)	$ (893.8)
Business and asset actions	(2,907.4)	(24.1)	(2,929.4)	(2,952.0)
Shareholder activism-related costs	0.0	(25.0)	0.0	(86.3)
Gain on sale of business	0.0	67.3	0.0	67.3
Equity affiliates' income	205.2	167.6	556.8	463.7
Interest expense	49.4	61.4	153.4	146.2
Other non-operating income (expense), net	3.6	(6.0)	3.1	14.3
Income (Loss) From Continuing Operations Before Taxes	(1,937.7)	890.8	(203.4)	(562.0)
Operating Segments
Segment Reporting [Line Items]
Operating income (loss)	810.3	741.1	2,319.5	2,045.9
Equity affiliates' income	205.2	167.6	556.8	470.5
Segment Reconciling Items
Segment Reporting [Line Items]
Business and asset actions	(2,907.4)	(24.1)	(2,929.4)	(2,952.0)
Shareholder activism-related costs	0.0	(25.0)	0.0	(86.3)
Gain on sale of business	0.0	67.3	0.0	67.3
Gain on sale of other assets	$ 0.0	$ 31.3	$ 0.0	$ 31.3