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Long-Term Debt and Short-Term Borrowings - Schedule of Long-Term Debt (Detail) - USD ($) $ in Thousands	Sep. 30, 2021	Mar. 18, 2021	Dec. 31, 2020	Aug. 13, 2015
Debt Instrument [Line Items]
Total long-term debt	$ 1,853,490		$ 1,387,743
Less: current maturities of long-term debt	0		1,514
Less: unamortized debt issuance costs	9,641		6,027
Long-term debt, net of current maturities	1,843,849		1,380,202
Senior secured term loans
Debt Instrument [Line Items]
Total long-term debt	$ 763,070		788,759
Senior secured term loans \| Minimum
Debt Instrument [Line Items]
Interest rate	0.75%
Senior secured term loans \| Maximum
Debt Instrument [Line Items]
Interest rate	1.15%
Other
Debt Instrument [Line Items]
Total long-term debt	$ 0		1,514
4.875% Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Interest rate	4.875%			4.875%
Total long-term debt	$ 597,799		$ 597,470
2.5% Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Interest rate	2.50%	2.50%	2.50%
Total long-term debt	$ 492,621		$ 0