Segment Information - Schedule of Segment Reporting Information By Segment (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jan. 31, 2018	Jan. 31, 2017	Jan. 31, 2018	Jan. 31, 2017
Segment Reporting Information [Line Items]
Sales to External Customers	$ 287,780	$ 268,001	$ 577,931	$ 548,177
Segment Profit	41,143	35,020	83,425	74,539
Id Solutions [Member]
Segment Reporting Information [Line Items]
Sales to External Customers	206,432	190,962	416,137	392,226
Segment Profit	34,088	28,961	69,925	62,035
Workplace Safety [Member]
Segment Reporting Information [Line Items]
Sales to External Customers	81,348	77,039	161,794	155,951
Segment Profit	$ 7,055	$ 6,059	$ 13,500	$ 12,504