Property and Equipment - Schedule of Property and Equipment (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Property, Plant and Equipment [Line Items]
Property Plant And Equipment Gross	$ 156,724	$ 128,549
Less: accumulated depreciation and amortization	(88,936)	(70,957)
Property Plant And Equipment Net	67,788	57,592
Land [Member]
Property, Plant and Equipment [Line Items]
Property Plant And Equipment Gross	66	66
Building [Member]
Property, Plant and Equipment [Line Items]
Property Plant And Equipment Gross	218	218
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property Plant And Equipment Gross	5,235	4,431
Furniture, Fixtures and Equipment[Member]
Property, Plant and Equipment [Line Items]
Property Plant And Equipment Gross	26,344	23,177
Vehicles and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property Plant And Equipment Gross	$ 124,861	$ 100,657