Long-term Debt - Schedule of Maturities of Debt (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Debt Disclosure [Abstract]
Term loans, in effect, net of unamortized debt issuance costs of $4,940 and $5,146, respectively	$ 292,810	$ 293,354
Vehicle and equipment notes, maturing March 2023; payable in various monthly installments, including interest rates ranging from 2% to 4.5%	51,556	50,357
Various notes payable, maturing through March 2025; payable in various monthly installments, including interest rates ranging from 4% to 5%	3,691	3,866
Total long term debt	348,057	347,577
Total long term debt	348,057	347,577
Less: current maturities	(17,378)	(16,650)
Long-term debt, less current maturities	$ 330,679	$ 330,927