Goodwill and Other Intangible Assets (Intangible Assets, Net) (Detail) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Goodwill and Other Intangible Assets [Line Items]
Intangible assets subject to amortization, gross	$ 109,741	$ 109,742
Less accumulated amortization	45,223	42,997
Intangible assets subject to amortization, net	64,518	66,745
Customer relationships
Goodwill and Other Intangible Assets [Line Items]
Intangible assets subject to amortization, gross	92,660	92,660
Non-compete agreements
Goodwill and Other Intangible Assets [Line Items]
Intangible assets subject to amortization, gross	13,057	13,057
Trade names
Goodwill and Other Intangible Assets [Line Items]
Intangible assets subject to amortization, gross	1,939	1,939
Other intangible assets
Goodwill and Other Intangible Assets [Line Items]
Intangible assets subject to amortization, gross	$ 2,085	$ 2,086