v3.26.1
Restructuring (Details) - USD ($)
$ in Millions
 3 Months Ended 9 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Restructuring Cost and Reserve [Line Items]        
Total restructuring and related costs $ 14.4 $ 8.0 $ 76.8 $ 45.9
Location, Statement of Income, Balance [Axis]: us-gaap:CostOfGoodsAndServicesSold | US Manufacturing Efficiency Initiatives        
Restructuring Cost and Reserve [Line Items]        
Total restructuring and related costs 3.8 0.0 14.9 0.0
Location, Statement of Income, Balance [Axis]: us-gaap:SellingGeneralAndAdministrativeExpense | IT enablement        
Restructuring Cost and Reserve [Line Items]        
Total restructuring and related costs 0.0 1.7 0.0 13.2
Project Momentum Restructuring        
Restructuring Cost and Reserve [Line Items]        
Total restructuring and related costs 10.6 6.3 61.9 32.7
Project Momentum Restructuring | Location, Statement of Income, Balance [Axis]: us-gaap:CostOfGoodsAndServicesSold        
Restructuring Cost and Reserve [Line Items]        
Severance and related benefit costs 0.6 0.1 2.7 0.3
Accelerated depreciation & fixed asset write-offs 0.0 0.0 22.0 3.3
Other restructuring related costs 3.1 2.8 10.3 17.4
Project Momentum Restructuring | Location, Statement of Income, Balance [Axis]: us-gaap:OtherNonoperatingIncomeExpense        
Restructuring Cost and Reserve [Line Items]        
Other restructuring related costs 0.0 0.0 0.0 (0.3)
Project Momentum Restructuring | Location, Statement of Income, Balance [Axis]: us-gaap:SellingGeneralAndAdministrativeExpense        
Restructuring Cost and Reserve [Line Items]        
Severance and related benefit costs 5.6 1.6 24.0 3.7
Accelerated depreciation & fixed asset write-offs 0.0 0.0 0.0 0.9
Other restructuring related costs $ 1.3 $ 1.8 $ 2.9 $ 7.4