Debt Instruments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Long-term debt, gross	$ 2,179,375	$ 1,685,000
Less current portion	(7,500)	(5,625)
Long term debt, gross, excluding current maturities	2,171,875	1,679,375
Less debt issuance costs and original issue discount	(25,992)	(21,807)
Total long-term debt	$ 2,145,883	$ 1,657,568
U.S. term loan averaging 4.01% in 2019; 3.83% in 2018 (due 2017-2024)
Debt Instrument [Line Items]
Interest rate during period	4.01%	3.83%
Total long-term debt	$ 729,375
2024 U.S. fixed rate notes at 5.375%
Debt Instrument [Line Items]
Stated interest rate percentage	5.375%
Long-term debt, gross	$ 450,000	$ 450,000
2027 U.S. fixed rate notes at 5.375%
Debt Instrument [Line Items]
Stated interest rate percentage	5.375%
Long-term debt, gross	$ 500,000	500,000
2029 U.S. fixed rate notes at 5.250%
Debt Instrument [Line Items]
Stated interest rate percentage	5.25%
Long-term debt, gross	$ 500,000	0
Senior Secured Term Loan | U.S. term loan averaging 4.01% in 2019; 3.83% in 2018 (due 2017-2024)
Debt Instrument [Line Items]
Long-term debt, gross	$ 729,375	$ 735,000