Summary of Significant Accounting and Reporting Policies (Sales by Geography and Customer Type (Details) - Net sales	12 Months Ended
Jul. 31, 2020	Jul. 31, 2019	Jul. 31, 2018
Geographic Concentration Risk
Concentration Risk [Line Items]
Concentration risk, percentage	100.00%	100.00%	100.00%
U.S. government \| Geographic Concentration Risk
Concentration Risk [Line Items]
Concentration risk, percentage	36.20%	40.10%	35.50%
Domestic \| Geographic Concentration Risk
Concentration Risk [Line Items]
Concentration risk, percentage	40.30%	34.50%	38.90%
Total United States \| Geographic Concentration Risk
Concentration Risk [Line Items]
Concentration risk, percentage	76.50%	74.60%	74.40%
International \| Geographic Concentration Risk
Concentration Risk [Line Items]
Concentration risk, percentage	23.50%	25.40%	25.60%
Verizon Communications Inc. \| Customer Concentration Risk
Concentration Risk [Line Items]
Concentration risk, percentage	10.00%	10.00%	10.00%

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 42
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e9054-108599

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=121572278&loc=d3e13531-108611

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6404-108592

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