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
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-Name Accounting Standards Codification
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Revenue Recognition (Sales by Geography and Customer Type (Details) - Net sales	3 Months Ended		6 Months Ended
	Jan. 31, 2021	Jan. 31, 2020	Jan. 31, 2021	Jan. 31, 2020	Jan. 31, 2019
Geographic Concentration Risk
Concentration Risk [Line Items]
Concentration risk, percentage	100.00%	100.00%	100.00%	100.00%
Geographic Concentration Risk \| U.S. government
Concentration Risk [Line Items]
Concentration risk, percentage	44.20%	41.50%	38.80%	41.20%
Geographic Concentration Risk \| Domestic
Concentration Risk [Line Items]
Concentration risk, percentage	33.90%	36.60%	37.60%	36.30%
Geographic Concentration Risk \| Total United States
Concentration Risk [Line Items]
Concentration risk, percentage	78.10%	78.10%	76.40%	77.50%
Geographic Concentration Risk \| International
Concentration Risk [Line Items]
Concentration risk, percentage	21.90%	21.90%	23.60%	22.50%
Customer Concentration Risk \| Verizon Communications Inc.
Concentration Risk [Line Items]
Concentration risk, percentage	10.00%				11.10%