Depreciation and Amortization - Depreciation and Amortization Expense for Property and Equipment and Intangible Assets (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Property, Plant and Equipment [Line Items]
Total depreciation expense	$ 5,245	$ 4,987
Operating Expenses [Member]
Property, Plant and Equipment [Line Items]
Total depreciation expense	5,130	4,891
Corporate General and Administrative Expenses [Member]
Property, Plant and Equipment [Line Items]
Total depreciation expense	$ 115	$ 96