Income Taxes - Schedule of Differences between Income Tax Expense at Federal Statutory Rate and Actual Income Taxes (Detail) - USD ($) $ in Thousands	12 Months Ended
Jul. 31, 2019	Jul. 31, 2018	Jul. 31, 2017
Income Tax Disclosure [Abstract]
Provision at federal statutory rate	$ 38,779	$ 170,095	$ 194,735
Differences between U.S. federal statutory and foreign tax rates	1,478
U.S. state and local income taxes, net of federal benefit	4,642	14,255	11,021
Nondeductible compensation	2,401
Nondeductible acquisition costs	3,031
Nondeductible foreign currency forward contract loss on acquisition	14,863
Nontaxable foreign currency remeasurement gains	(12,942)
Federal income tax credits and incentives	(3,373)	(3,518)	(3,228)
Domestic production activities deduction		(16,175)	(19,527)
Change in uncertain tax positions	1,279	396	375
Effect of the U.S. Tax Act		38,620
Other	2,043	(795)	(1,244)
Total income tax expense	$ 52,201	$ 202,878	$ 182,132

Effective income tax rate reconciliation change in enacted tax rate tax reform amount.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of the difference between reported income tax expense (benefit) and the expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to deduction for qualified production activity.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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Amount of reported income tax expense (benefit) in excess of (less than) expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to nondeductible expense for award under share-based payment arrangement. Includes, but is not limited to, expense determined to be nondeductible upon grant or after for award under share-based payment arrangement.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to increase (decrease) in income tax contingencies. Including, but not limited to, domestic tax contingency, foreign tax contingency, state and local tax contingency, and other contingencies.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to tax credits. Including, but not limited to, research credit, foreign tax credit, investment tax credit, and other tax credits.

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