Long-term Debt Long Term Debt (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Less: unamortized debt issuance costs long-term	$ (33,186)	$ (23,508)
Debt and Capital Lease Obligations	2,359,453	2,281,751
Less: current portion, net of unamortized debt issuance costs	52,538	75,966
Long-term debt, less current portion	2,306,915	2,205,785
Credit Agreement [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 1,630,406	$ 2,177,724
Debt Instrument, Interest Rate, Stated Percentage	2.71%	2.60%
Debt Instrument, Maturity date	Mar. 31, 2020	Mar. 31, 2020
Australia Credit Agreement
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 498,801	$ 0
Debt Instrument, Interest Rate, Stated Percentage	4.64%
Debt Instrument, Maturity date	Dec. 01, 2021
Australian Partner Loan Agreement [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 172,154	0
Debt Instrument, Interest Rate, Stated Percentage	6.51%
Debt Instrument, Maturity date	Nov. 01, 2026
Other debt [Member]
Debt Instrument [Line Items]
Other debt and capital leases	$ 91,278	127,535
Other assets, net [Member] \| Accounting Standards Update 2015-03 [Member]
Debt Instrument [Line Items]
Less: unamortized debt issuance costs long-term		23,500
Current portion of long-term debt [Member] \| Accounting Standards Update 2015-03 [Member]
Debt Instrument [Line Items]
Less: unamortized debt issuance costs long-term		(6,000)
Long-term debt less current portion [Member] \| Accounting Standards Update 2015-03 [Member]
Debt Instrument [Line Items]
Less: unamortized debt issuance costs long-term		$ (17,500)

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.13,16)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
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Contractual interest rate for funds borrowed, under the debt agreement.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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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