Long-Term Debt - Schedule of Long-term Debt (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020	Jun. 30, 2020
Debt Instrument [Line Items]
Total debt - principal	$ 3,440,236	$ 3,271,969	$ 3,520,556
Less unamortized debt issuance costs and debt discount	22,984	20,716	22,713
Debt long term and short term less unamortized debt issuance costs combined amount	3,417,252	3,251,253	3,497,843
Less current portion	240,859	28,036	391,418
Long-term debt	3,176,393	3,223,217	3,106,425
Bank debt
Debt Instrument [Line Items]
Total debt - principal	642,991	930,407	1,296,534
Finance Leases
Debt Instrument [Line Items]
Total debt - principal	33,460	34,480	35,102
Bank Revolving Loans \| Bank debt
Debt Instrument [Line Items]
Total debt - principal	195,859	0	354,000
Less current portion	195,900
U S Term Loans \| Bank debt
Debt Instrument [Line Items]
Total debt - principal	400,000	900,000	900,000
Other Foreign Bank Revolving and Term Loans \| Bank debt
Debt Instrument [Line Items]
Total debt - principal	47,132	30,407	42,534
Less current portion	43,100
Senior Notes \| 4¾% Notes
Debt Instrument [Line Items]
Total debt - principal	300,000	300,000	300,000
Senior Notes \| 3¼% Notes
Debt Instrument [Line Items]
Total debt - principal	770,835	795,307	728,520
Senior Notes \| 4⅛% Notes
Debt Instrument [Line Items]
Total debt - principal	600,000	600,000	600,000
Senior Notes \| 2¼% Notes
Debt Instrument [Line Items]
Total debt - principal	592,950	611,775	560,400
Senior Notes \| 1.4% Notes
Debt Instrument [Line Items]
Total debt - principal	500,000	$ 0	$ 0
Finance Leases
Debt Instrument [Line Items]
Less current portion	$ 1,900

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Amount of unamortized debt discount (premium) and debt issuance costs.

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Represents the aggregate of total long-term debt, including current maturities and short-term 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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