Segment Information - Schedule of Segment Reporting Information By Segment (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Jul. 31, 2013	Apr. 30, 2013	Jan. 31, 2013	Oct. 31, 2012	Jul. 31, 2012	Apr. 30, 2012	Jan. 31, 2012	Oct. 31, 2011	Jul. 31, 2013	Jul. 31, 2012	Jul. 31, 2011
Segment Reporting Information [Line Items]
Revenues from external customers	$ 309,097	$ 300,971	$ 271,175	$ 270,866	$ 269,089	$ 271,151	$ 255,052	$ 273,396	$ 1,152,109	$ 1,068,688	$ 1,059,355
Depreciation and amortization									48,725	43,987	48,827
Total profit from reportable segments									266,560	276,614	265,037
Assets	1,438,683				1,607,719				1,438,683	1,607,719	1,861,505
Payments to Acquire Property, Plant, and Equipment									35,687	24,147	20,532
Identification Solutions [Member]
Segment Reporting Information [Line Items]
Revenues from external customers									733,433	633,774	625,396
Depreciation and amortization									25,920	18,253	19,252
Total profit from reportable segments									171,319	159,427	146,124
Assets	989,216				744,055				989,216	744,055	782,324
Payments to Acquire Property, Plant, and Equipment									18,186	15,213	13,406
Workplace Safety [Member]
Segment Reporting Information [Line Items]
Revenues from external customers									418,676	434,914	433,959
Depreciation and amortization									9,078	7,827	10,769
Total profit from reportable segments									95,241	117,187	118,913
Assets	239,219				439,255				239,219	439,255	444,354
Payments to Acquire Property, Plant, and Equipment									8,459	4,989	3,979
Corporate [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization									13,727	17,907	18,806
Assets	210,248				424,409				210,248	424,409	634,827
Payments to Acquire Property, Plant, and Equipment									$ 9,042	$ 3,945	$ 3,147