Fair Value Measurements - Additional Information (Detail) - USD ($) $ in Thousands	Jul. 31, 2017	Jul. 31, 2016	Jul. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Goodwill	$ 437,697	$ 429,871	$ 433,199
Property, Plant and Equipment, Net	98,103	102,444
Identification Solutions
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Goodwill	391,864	384,529	382,786
Workplace Safety
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Goodwill	$ 45,833	$ 45,342	$ 50,413