Derivative Financial Instruments Cross Currency Swap (Details) $ in Thousands, € in Millions, AUD in Millions	12 Months Ended
	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Dec. 01, 2016 AUD	Dec. 01, 2016 EUR (€)
Derivatives [Line Items]
Derivative instruments not designated as hedges amount recognized in earnings	$ 0	$ (18,686)	$ 0
Currency Swap [Member]
Derivatives [Line Items]
Derivative, Notional Amount				AUD 248.9	€ 171.7
Currency Swap 1 [Member]
Derivatives [Line Items]
Derivative, Notional Amount				123.9	85.5
Currency Swap 2 [Member]
Derivatives [Line Items]
Derivative, Notional Amount				125.0	€ 86.3
BBR Interest rate [Member] | Currency Swap 1 [Member]
Derivatives [Line Items]
Derivative, Description of Terms	Australian dollar BBR plus 4.50%
BBR Interest rate [Member] | Currency Swap 2 [Member]
Derivatives [Line Items]
Derivative, Description of Terms	Australian dollar BBR plus 4.50%
EURIBOR Interest Rate [Member] | Currency Swap 1 [Member]
Derivatives [Line Items]
Derivative, Description of Terms	EURIBOR plus 2.68%
EURIBOR Interest Rate [Member] | Currency Swap 2 [Member]
Derivatives [Line Items]
Derivative, Description of Terms	EURIBOR plus 2.90%
Intercompany Loan [Member]
Derivatives [Line Items]
Debt Instrument, Face Amount | AUD				AUD 248.9
Not Designated as Hedging Instrument [Member]
Derivatives [Line Items]
Derivative instruments not designated as hedges amount recognized in earnings	$ (3,267)	(18,686)	(1,270)
Not Designated as Hedging Instrument [Member] | Currency Swap [Member]
Derivatives [Line Items]
Derivative instruments not designated as hedges amount recognized in earnings	3,300
Other (expense)/income, net | Not Designated as Hedging Instrument [Member] | Currency Swap [Member]
Derivatives [Line Items]
Derivative instruments not designated as hedges amount recognized in earnings	$ (3,267)	$ 0	$ (86)