Supplemental Balance Sheet Information (Details) - USD ($) $ in Millions	Sep. 30, 2025	Sep. 30, 2024
Receivables, net
Accounts receivable, trade	$ 205.6	$ 205.6
Accounts receivable, other	18.2	15.1
Total receivables, gross	223.8	220.7
Allowance for doubtful accounts	(0.4)	(0.3)
Receivables, net	223.4	220.4
Inventories
Inventory, raw materials, net	88.3	57.3
Inventory, work in process	0.1	0.0
Inventory, finished goods, net	242.0	228.8
Inventories	330.4	286.1
Accounts Payable
Accounts payable, trade	115.1	119.1
Accounts Payable, Related Party, Name [Extensible Enumeration]	3.7	1.5
Accounts payable, other	0.7	0.4
Accounts payable	119.5	121.0
Other Current Liabilities
Estimated litigation liability, current	90.0	21.0
Accrued salaries, current	19.9	23.8
Derivative liability, current	$ 12.6	$ 0.1
Derivative liabilities	Other current liabilities	Other current liabilities
Accrued advertising and promotion expense	$ 9.7	$ 8.1
Other accrued liabilities, current	31.1	29.7
Other current liabilities	$ 163.3	$ 82.7