Intangible Assets - Schedule of Changes in the Carrying Amounts of Intangible Assets (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Finite-lived Intangible Assets [Roll Forward]
Beginning Balance	$ 86,862
Amortization	(2,438)	$ (2,471)
Ending Balance	84,424
Customer Relationships [Member]
Finite-lived Intangible Assets [Roll Forward]
Beginning Balance	82,044
Amortization	(2,171)
Ending Balance	$ 79,873
Weighted average remaining amortization period	9 years 2 months
Trademark / Tradename [Member]
Finite-lived Intangible Assets [Roll Forward]
Beginning Balance	$ 4,818
Amortization	(267)
Ending Balance	$ 4,551
Weighted average remaining amortization period	4 years 3 months 24 days