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Provision for Income Taxes (Detail) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
	Feb. 01, 2019	Apr. 30, 2020	Apr. 30, 2019	Apr. 30, 2020	Apr. 30, 2019
Income Tax Contingency [Line Items]
Effective income tax rate		(7.30%)	24.30%	18.50%	46.60%
Expected decrease in unrecognized tax benefits due to resolution of uncertain tax positions		$ 4,700		$ 4,700
Accrued interest		1,300		1,300
Foreign currency transaction gain (loss)		$ 6,293		$ 9,136
Not Designated as Hedging Instrument
Income Tax Contingency [Line Items]
Foreign currency transaction gain (loss)	$ (70,777)
Erwin Hymer Group \| Not Designated as Hedging Instrument
Income Tax Contingency [Line Items]
Foreign currency transaction gain (loss)			$ 2,930		$ (70,777)