Acquisitions - Summary of Allocation of Acquisition Costs (Detail) $ in Thousands	6 Months Ended
	Jun. 30, 2016 USD ($)
Business Acquisition [Line Items]
Property, plant and equipment	$ 93,814
Goodwill	158,341
Current assets	4,674
Other assets	2,046
Current liabilities	(5,238)
Total	515,147
Site Locations [Member]
Business Acquisition [Line Items]
Finite lived intangible assets	222,176
Non-competition Agreements [Member]
Business Acquisition [Line Items]
Finite lived intangible assets	40
Customer Lists and Contracts [Member]
Business Acquisition [Line Items]
Finite lived intangible assets	$ 39,294