Long-term Debt Unamortized Deferred Financing Fees (Details) $ in Thousands, AUD in Millions	12 Months Ended
	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2016 AUD	Dec. 31, 2016 USD ($)
Debt Issuance Costs, Gross		$ 28,248			$ 42,495
Accumulated Amortization, Debt Issuance Costs		(4,740)			(9,309)
Debt Issuance Costs, Net		$ 23,508			33,186
Debt Issuance Cost, Weighted Average Amortization Period	3 years	4 years
Amortization of Debt Issuance Costs	$ 7,700	$ 7,600	$ 12,200
2017					8,957
2018					8,815
2019					8,638
2020					4,173
2021					2,603
Credit Agreement [Member]
Debt Issuance Costs, Gross		5,800	3,700		3,000
Write off of Deferred Debt Issuance Cost	$ 1,300	$ 2,000	$ 4,600
Australia Credit Agreement
Debt Issuance Costs, Gross				AUD 19.8	$ 14,700