Concentration of Risk - Additional Information (Detail) - Customer Concentration Risk - Freedom Roads, LLC	12 Months Ended
Jul. 31, 2019	Jul. 31, 2018	Jul. 31, 2017
Net Sales
Concentration Risk [Line Items]
Concentration risk percentage	18.50%	20.00%	20.00%
Accounts Receivable
Concentration Risk [Line Items]
Concentration risk percentage	19.00%	26.00%

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://fasb.org/us-gaap/role/ref/legacyRef
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