Long-Term Debt - Summary of Long-Term Debt, Net (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Long-term debt	$ 2,216,002	$ 2,219,878
Less: unamortized discounts and debt issuance costs	(25,519)	(27,236)
Less: current maturities	(15,505)	(15,505)
Total long-term debt, net	2,174,978	2,177,137
Senior Notes [Member]
Debt Instrument [Line Items]
Long-term debt	227,500	227,500
Term B-5 Loans [Member]
Debt Instrument [Line Items]
Long-term debt	1,488,502	1,492,378
Second-Priority Senior Notes [Member]
Debt Instrument [Line Items]
Long-term debt	$ 500,000	$ 500,000

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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Amount of unamortized debt discount (premium) and debt issuance costs.

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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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