Segment Information - Schedule of Segment Reporting Information By Segment (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Jul. 31, 2015	Apr. 30, 2015	Jan. 31, 2015	Oct. 31, 2014	Jul. 31, 2014	Apr. 30, 2014	Jan. 31, 2014	Oct. 31, 2013	Jul. 31, 2015	Jul. 31, 2014	Jul. 31, 2013
Segment Reporting Information [Line Items]
Revenues to external customers	$ 288,636	$ 290,227	$ 282,628	$ 310,240	$ 316,733	$ 309,577	$ 291,194	$ 307,530	$ 1,171,731	$ 1,225,034	$ 1,157,792
Depreciation and amortization									39,458	44,598	48,725
Segment profit									206,342	242,367	269,631
Assets	1,062,897				1,253,665				1,062,897	1,253,665	1,438,683
Payments to Acquire Property, Plant, and Equipment									26,673	43,398	35,687
Identification Solutions
Segment Reporting Information [Line Items]
Revenues to external customers									806,484	825,123	739,116
Depreciation and amortization									25,658	28,955	25,920
Segment profit									149,840	176,129	174,390
Assets	780,524				882,440				780,524	882,440	989,216
Payments to Acquire Property, Plant, and Equipment									18,732	28,774	18,186
Workplace Safety
Segment Reporting Information [Line Items]
Revenues to external customers									365,247	399,911	418,676
Depreciation and amortization									6,772	7,919	9,078
Segment profit									56,502	66,238	95,241
Assets	167,797				239,848				167,797	239,848	239,219
Payments to Acquire Property, Plant, and Equipment									3,970	10,580	8,459
Corporate [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization									7,028	7,724	13,727
Assets	$ 114,576				$ 131,377				114,576	131,377	210,248
Payments to Acquire Property, Plant, and Equipment									$ 3,971	$ 4,044	$ 9,042