Debt - Summary of Long-Term Debt and Related Weighted Average Interest Rates (Detail) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Total Debt	$ 624,223	$ 643,184
Debt Issuance Costs	(8,481)	(11,580)
Total Debt, Net	615,742	631,604
Less: Current portion	(6,297)	(6,112)
Long-term debt	609,445	625,492
Term Loan Facility [Member]
Debt Instrument [Line Items]
Total Debt	349,200	349,200
Debt Issuance Costs	(4,794)	(7,155)
Total Debt, Net	$ 344,406	$ 342,045
Weighted Average Interest Rate	4.10%	4.10%
Senior Notes [Member] \| 6.00% Senior Notes [Member]
Debt Instrument [Line Items]
Total Debt	$ 251,735	$ 266,928
Debt Issuance Costs	(3,687)	(4,425)
Total Debt, Net	$ 248,048	$ 262,503
Weighted Average Interest Rate	6.00%	6.00%
European CapEx Loans [Member]
Debt Instrument [Line Items]
Total Debt	$ 20,348	$ 23,668
Total Debt, Net	$ 20,348	$ 23,668
Weighted Average Interest Rate	2.30%	2.30%
Finance Leases [Member]
Debt Instrument [Line Items]
Total Debt	$ 2,940	$ 3,388
Total Debt, Net	$ 2,940	$ 3,388
Weighted Average Interest Rate	2.80%	3.00%

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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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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