Other Income (Loss), Net - Schedule of Other Income (Loss) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Long Lived Assets Held-for-sale [Line Items]
Interest income	$ 1,525	$ 1,822	$ 1,142
Gain on asset dispositions, net	1,724	2,094	436
Land impairment loss	0	(50)	(1,557)
Disposal of non-core product lines	(4,223)	0	0
Impairment of intangible assets	(723)	0	0
Other, net	836	(1,101)	(196)
Total	(861)	2,765	$ (175)
Safety Works
Long Lived Assets Held-for-sale [Line Items]
Impairment of intangible assets	(700)
Property in Australia
Long Lived Assets Held-for-sale [Line Items]
Gain on asset dispositions, net	2,000
Detector Tube Assets
Long Lived Assets Held-for-sale [Line Items]
Gain on asset dispositions, net		$ 2,200
North American Segment | Safety Works
Long Lived Assets Held-for-sale [Line Items]
Disposal of non-core product lines	$ (4,200)