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Long-Term Debt - Schedule of Long-term Debt (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Sep. 14, 2018	Dec. 31, 2017	Nov. 03, 2016	Aug. 31, 2013
Debt Instrument [Line Items]
Capital Leases	$ 1,677		$ 2,324
Total	3,865,099		1,870,528
Less - current portion	47,038		47,225
Long-term portion	3,818,061		1,823,303
Revolving Credit Facility
Debt Instrument [Line Items]
Unamortized discount and debt issuance cost	3,412		2,451
Line of Credit \| Revolving Credit Facility
Debt Instrument [Line Items]
Long-term debt	346,588		853,124
Other Borrowings
Debt Instrument [Line Items]
Long-term debt	29,721		6,860
Floating Rate Senior Notes
Debt Instrument [Line Items]
Long-term debt	496,495		0
Floating Rate Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Long-term debt	496,495		0
Unamortized discount and debt issuance cost	3,505
Senior Notes due 2024
Debt Instrument [Line Items]
Long-term debt	$ 742,616		0
Stated interest rate (as a percent)	4.15%
Senior Notes due 2024 \| Senior Notes
Debt Instrument [Line Items]
Long-term debt	$ 742,616		0
Stated interest rate (as a percent)		4.15%
Unamortized discount and debt issuance cost	7,384
Senior Notes due 2028
Debt Instrument [Line Items]
Long-term debt	$ 1,239,417		0
Stated interest rate (as a percent)	4.70%
Senior Notes due 2028 \| Senior Notes
Debt Instrument [Line Items]
Long-term debt	$ 1,239,417		0
Stated interest rate (as a percent)		4.70%
Unamortized discount and debt issuance cost	10,583
Senior Notes Due 2026
Debt Instrument [Line Items]
Long-term debt	$ 748,225		747,655
Stated interest rate (as a percent)	3.45%
Senior Notes Due 2026 \| Senior Notes
Debt Instrument [Line Items]
Long-term debt	$ 748,225		747,655
Stated interest rate (as a percent)				3.45%
Unamortized discount and debt issuance cost	1,775		2,345
4.375% Senior Notes, due 2023
Debt Instrument [Line Items]
Long-term debt	$ 248,759		248,567
Stated interest rate (as a percent)	4.375%
4.375% Senior Notes, due 2023 \| Senior Notes
Debt Instrument [Line Items]
Long-term debt	$ 248,759		248,567
Stated interest rate (as a percent)					4.375%
Unamortized discount and debt issuance cost	1,241		1,433
Schuldschein Loan
Debt Instrument [Line Items]
Long-term debt	$ 11,601		$ 11,998