Acquisitions - Summary of Preliminary Estimated Fair Values of Assets Acquired and Liabilities Assumed (Detail) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015	Oct. 30, 2015	Oct. 08, 2015	Jun. 17, 2015	Feb. 04, 2015
Business Acquisition [Line Items]
Goodwill	$ 867,623	$ 858,532
RMS
Business Acquisition [Line Items]
Current assets			$ 3,605
Property, plant & equipment			1,378
Goodwill			8,847
Other intangible assets			8,621
Other assets			0
Total assets acquired			22,451
Total liabilities assumed			(3,741)
Net assets acquired			$ 18,710
Track IQ
Business Acquisition [Line Items]
Current assets				$ 660
Property, plant & equipment				187
Goodwill				6,649
Other intangible assets				3,246
Other assets				0
Total assets acquired				10,742
Total liabilities assumed				(1,430)
Net assets acquired				$ 9,312
MTC
Business Acquisition [Line Items]
Current assets					$ 10,906
Property, plant & equipment					1,510
Goodwill					12,141
Other intangible assets					7,649
Other assets					114
Total assets acquired					32,320
Total liabilities assumed					(8,960)
Net assets acquired					$ 23,360
RCL
Business Acquisition [Line Items]
Current assets						$ 16,421
Property, plant & equipment						12,136
Goodwill						14,787
Other intangible assets						40,403
Other assets						0
Total assets acquired						83,747
Total liabilities assumed						(5,736)
Net assets acquired						$ 78,011