Long-term Debt Long Term Debt (Details) $ in Thousands, $ in Millions	12 Months Ended
Dec. 31, 2018 AUD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Debt Instrument [Line Items]
Less: unamortized debt issuance costs long-term		$ (20,108)	$ (25,175)
Long-term debt		2,453,538	2,331,295
Less: current portion, net of unamortized debt issuance costs		28,303	27,853
Long-term debt, less current portion		2,425,235	2,303,442
Credit Agreement [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross		$ 1,783,423	$ 1,567,882
Debt Instrument, Interest Rate, Stated Percentage	3.70%	3.70%	2.82%
Debt Instrument, Maturity date	Jun. 05, 2023
Australia Credit Agreement
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 650.3	$ 458,166	$ 525,101
Debt Instrument, Interest Rate, Stated Percentage	4.56%	4.56%	4.28%
Debt Instrument, Maturity date	Dec. 01, 2021
Partner Loan Agreement [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross		$ 167,796	$ 186,085
Debt Instrument, Interest Rate, Stated Percentage	6.72%	6.72%	6.50%
Debt Instrument, Maturity date	Nov. 01, 2026
Other debt and capital leases [Member]
Debt Instrument [Line Items]
Other debt and capital leases		$ 64,261	$ 77,402

Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

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Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

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