Acquisitions - Summary of Preliminary Estimated Fair Values of Assets Acquired and Liabilities Assumed (Detail) - USD ($) $ in Thousands	Jun. 30, 2016	May 05, 2016	Dec. 31, 2015	Oct. 30, 2015	Oct. 08, 2015	Jun. 17, 2015	Feb. 04, 2015
Business Acquisition [Line Items]
Goodwill	$ 860,027		$ 858,532
Unitrac
Business Acquisition [Line Items]
Current assets		$ 12,526
Property, plant & equipment		1,768
Goodwill		998
Other intangible assets		1,230
Other assets		0
Total assets acquired		16,522
Total liabilities assumed		(2,144)
Net assets acquired		$ 14,378
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						$ 10,348
Property, plant & equipment						1,450
Goodwill						13,198
Other intangible assets						7,650
Other assets						114
Total assets acquired						32,760
Total liabilities assumed						(9,400)
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