Long-Term Debt - Summary of Long-Term Debt, Net (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Long-term debt	$ 2,219,878	$ 1,557,883
Less: discounts and debt issuance costs	(27,236)	(9,759)
Less: current maturities, including revolving credit facility at December 31, 2019	(15,505)	(65,505)
Total long-term debt, net	2,177,137	1,482,619
Senior Notes [Member]
Debt Instrument [Line Items]
Long-term debt	227,500
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Long-term debt		50,000
Term B-5 Loans [Member]
Debt Instrument [Line Items]
Long-term debt	1,492,378	$ 1,507,883
Second-Priority Senior Notes [Member]
Debt Instrument [Line Items]
Long-term debt	$ 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, 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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