Supplemental Financial Statement Information (Supplemental Balance Sheet Information) (Details) - USD ($) $ in Millions	Mar. 31, 2024	Sep. 30, 2023
Inventories
Raw materials and supplies	$ 142.5	$ 113.5
Work in process	215.1	258.5
Finished products	308.5	277.7
Total inventories	666.1	649.7
Other Current Assets
Miscellaneous receivables	33.8	20.8
Prepaid expenses	103.9	83.6
Value added tax collectible from customers	29.1	30.6
Other	33.4	37.0
Total other current assets	200.2	172.0
Property, Plant and Equipment
Land	12.9	12.9
Buildings	138.9	135.2
Machinery and equipment	846.1	832.9
Construction in progress	77.6	69.7
Finance Leases	55.1	39.2
Total gross property	1,130.6	1,089.9
Accumulated depreciation	(743.7)	(726.2)
Property, plant and equipment, net	386.9	363.7
Other Current Liabilities
Accrued advertising, sales promotion and allowances	13.3	12.9
Accrued trade allowances	29.2	52.7
Accrued freight and warehousing	30.3	35.1
Accrued freight and warehousing	39.7	57.9
Accrued salaries, vacations and incentive compensation	20.4	20.5
Restructuring and related cost reserve	12.2	17.1
Income taxes payable	29.0	36.9
Other	100.8	92.5
Total other current liabilities	274.9	325.6
Other Liabilities
Pensions and other retirement benefits	55.6	55.0
Deferred compensation	15.7	17.4
Mandatory transition tax	7.1	12.8
Restructuring and related cost reserve	2.3	2.5
Other non-current liabilities	33.0	47.8
Other liabilities	$ 113.7	$ 135.5