Income Taxes (Schedule of Reconciliation of U.S. Statutory Income Tax Rate With Effective Income Tax Rate) (Details)	12 Months Ended
Jul. 31, 2020	Jul. 31, 2019	Jul. 31, 2018
Income Tax Disclosure [Abstract]
Statutory U.S. federal rate (percentage)	21.00%	21.00%	26.90%
State income taxes (percentage)	0.90%	1.30%	0.90%
Foreign operations (percentage)	3.50%	4.70%	1.70%
Global Intangible Low Tax Income (GILTI) (percentage)	0.20%	1.30%
Foreign Derived Intangible Income (FDII) (percentage)	(1.40%)	(1.40%)
Export, manufacturing and research credits (percentage)	(0.70%)	(0.80%)	(1.00%)
Change in unrecognized tax benefits (percentage)	0.60%	(0.80%)	(0.30%)
Tax benefits on stock-based compensation (percentage)	(1.20%)	(1.60%)	(1.20%)
Impact of U.S. Tax Cuts and Jobs Act (percentage)	0.00%	5.00%	23.20%
Other (percentage)	0.40%	0.10%	0.20%
Effective income tax rate (percentage)	23.30%	28.80%	50.40%

Change In Unrecognized Tax Benefits

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Effective Income Tax Rate Reconciliation, Impact of US Tax Cuts and Jobs Act, Percent

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Effective Income Tax Rate Reconciliation, Tax Cuts And Jobs Act Of 2017, Foreign Derived Intangible Income, Percent

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- Definition

Effective Income Tax Rate Reconciliation, Tax Cuts And Jobs Act Of 2017, Global Intangible Low Tax Income, Percent

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 6.I.Fact.4)
-URI http://asc.fasb.org/extlink&oid=116825942&loc=d3e330036-122817

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319

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Percentage 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 applicable to statutory income tax expense (benefit) outside of the country of domicile.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319

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-Name Accounting Standards Codification
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-Section S99
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-Subparagraph (SAB Topic 6.I.Fact.4)
-URI http://asc.fasb.org/extlink&oid=116825942&loc=d3e330036-122817

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Percentage of difference between reported income tax expense (benefit) and 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 share-based payment arrangement.

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Percentage 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 applicable to state and local income tax expense (benefit), net of federal tax expense (benefit).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 6.I.Fact.4)
-URI http://asc.fasb.org/extlink&oid=116825942&loc=d3e330036-122817

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319

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Percentage 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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