Debt - Summary of Long-Term Debt and Related Weighted Average Interest Rates (Detail) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Total Debt	$ 695,116
Debt Issuance Costs	(22,384)
Total Debt, Net	672,732
Less: Current portion	3,112	$ 4,000
Long-term debt	669,620	$ 679,552
Term Loan Facility [Member]
Debt Instrument [Line Items]
Total Debt	384,800
Debt Issuance Costs	(14,443)
Total Debt, Net	$ 370,357
Weighted Average Interest Rate	6.10%
Senior Notes [Member] \| Senior Notes, 6.00%, due 2025 [Member]
Debt Instrument [Line Items]
Total Debt	$ 291,650
Debt Issuance Costs	(7,941)
Total Debt, Net	$ 283,709
Weighted Average Interest Rate	6.00%
Other [Member]
Debt Instrument [Line Items]
Total Debt	$ 18,666
Total Debt, Net	$ 18,666
Weighted Average Interest Rate	1.90%

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Weighted average interest rate of debt outstanding.

+ References

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- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

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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