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Restructuring (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
Restructuring (Details) - USD ($) $ in Millions	Apr. 30, 2021	Jan. 31, 2021	Apr. 30, 2021
Restructuring Cost and Reserve
Payments for restructuring	$ 1.5		$ 2.0
Accrued restructuring expenses	$ 12.8		12.8
Cost of Sales
Restructuring Cost and Reserve
Restructuring charges			5.8
Cost of Sales \| Corporate and unallocated
Restructuring Cost and Reserve
Restructuring charges			5.8
Operating Expense
Restructuring Cost and Reserve
Restructuring charges			9.0
Operating Expense \| Engine Products segment
Restructuring Cost and Reserve
Restructuring charges			2.5
Operating Expense \| Industrial Products segment
Restructuring Cost and Reserve
Restructuring charges			$ 6.5
Employee Severance
Restructuring Cost and Reserve
Restructuring charges		$ 14.8