Income Taxes (Schedule of Temporary Differences That Give Rise to Deferred Tax Assets and Liabilities) (Details) - USD ($) $ in Millions	Jul. 31, 2020	Jul. 31, 2019	Jul. 31, 2018	Jul. 31, 2017
Deferred tax assets:
Accrued expenses	$ 9.9	$ 10.1
Compensation and retirement plans	31.8	27.9
NOL and tax credit carryforwards	8.1	4.4
Inventory reserves	3.4	3.0
Operating lease assets	18.8
Other	4.2	4.5
Gross deferred tax assets	76.2	49.9
Valuation allowance	(8.1)	(4.4)	$ (6.2)	$ (5.2)
Deferred tax assets, net of valuation allowance	68.1	45.5
Deferred tax liabilities:
Depreciation and amortization	(47.4)	(43.2)
Operating lease liabilities	(18.8)
Other	(1.8)	(1.4)
Deferred tax liabilities	(68.0)	(44.6)
Net deferred tax asset	$ 0.1	$ 0.9