Long-term Debt - Schedule of Maturities of Debt (Detail) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Debt Disclosure [Abstract]
Term loan, net of unamortized debt issuance costs of $5,213 and $5,146, respectively	$ 392,537	$ 293,354
Vehicle and equipment notes, maturing June 2023; payable in various monthly installments, including interest rates ranging from 2.5% to 4.6%	57,603	50,357
Various notes payable, maturing through March 2025; payable in various monthly installments, including interest rates ranging from 4% to 5%	3,267	3,866
Total long term debt	453,407	347,577
Total long term debt	453,407	347,577
Less: current maturities	(20,083)	(16,650)
Long-term debt, less current maturities	$ 433,324	$ 330,927

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Carrying value as of the balance sheet date of loans payable (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion.

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Carrying value as of the balance sheet date of notes payable (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion.

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Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

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