Debt - Summary of Total Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Aug. 21, 2018
Debt Instrument [Line Items]
Total debt	$ 1,155,007	$ 1,373,155
Debt issuance costs	(17,103)	(21,905)
Less: current portion of term loans	34,265	34,148
Less: current portion of debt issuance costs	(4,685)	(4,802)
Total long-term debt	1,120,742	1,339,007
Term Loans
Debt Instrument [Line Items]
Total debt	717,110	756,060
Less: current portion of term loans	38,950	38,950
Line of Credit \| Revolving Credit Facility
Debt Instrument [Line Items]
Total debt	55,000	239,000
Senior Notes \| 5.750% Senior Notes, due August 2026
Debt Instrument [Line Items]
Total debt	$ 400,000	$ 400,000
Stated interest rate (percentage)			5.75%

Contractual interest rate for funds borrowed, under the debt agreement.

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

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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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