Debt - Summary of Long-Term Debt and Related Weighted Average Interest Rates (Detail) - USD ($) $ in Thousands	Sep. 30, 2019	Jun. 30, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Total Debt	$ 634,745		$ 684,922
Debt Issuance Costs	(16,763)		(20,444)
Total Debt, Net	617,982		664,478
Less: Current portion	(3,300)		(3,052)
Long-term debt	614,682		661,426
Term Loan Facility [Member]
Debt Instrument [Line Items]
Total Debt	375,800		382,800
Debt Issuance Costs	(10,953)		(13,078)
Total Debt, Net	$ 364,847		$ 369,722
Weighted Average Interest Rate	6.10%		6.30%
Senior Notes [Member] \| Senior Notes, 6.00%, due 2025 [Member]
Debt Instrument [Line Items]
Total Debt	$ 243,962		$ 286,100
Debt Issuance Costs	(5,810)		(7,366)
Total Debt, Net	$ 238,152		$ 278,734
Weighted Average Interest Rate	6.00%		6.00%
Long-term debt	$ 7,600	$ 21,800
Other [Member]
Debt Instrument [Line Items]
Total Debt	13,183		$ 16,022
Total Debt, Net	$ 13,183		$ 16,022
Weighted Average Interest Rate	2.20%		2.20%
Capital Leases [Member]
Debt Instrument [Line Items]
Total Debt	$ 1,800
Total Debt, Net	$ 1,800
Weighted Average Interest Rate	2.90%

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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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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Weighted average interest rate of debt outstanding.

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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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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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