Long-Term Debt and Short-Term Borrowings - Schedule of Long-Term Debt (Detail) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Total long-term debt	$ 1,774,469	$ 1,784,921
Less: current maturities of long-term debt	(2,573)	(3,146)
Less: unamortized debt issuance costs	(11,715)	(14,515)
Total long-term debt, net of current maturities	1,760,181	1,767,260
Senior secured term loans [Member]
Debt Instrument [Line Items]
Total long-term debt	748,632	758,452
Other Long Term Debt [Member]
Debt Instrument [Line Items]
Total long-term debt	2,998	3,682
4.875% Senior Notes [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Total long-term debt	596,750	596,653
5.25% Senior Notes [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Total long-term debt	$ 426,089	$ 426,134

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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