Derivative Financial Instruments and Hedging Activities Schedule of Derivative Instruments in Statement of Financial Position (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013
Derivatives, Fair Value [Line Items]
Derivative Liability	$ (4,873)	[1]
Prepaid and other current assets
Derivatives, Fair Value [Line Items]
Derivative Asset	1,781	[1]
Other current liabilities
Derivatives, Fair Value [Line Items]
Derivative Liability	(214)	[1]
Other non-current liabilities
Derivatives, Fair Value [Line Items]
Derivative Liability	(4,659)	[1]
Designated as Hedging Instrument [Member] | Cash Flow Hedging [Member] | Foreign currency exchange contracts [Member] | Prepaid and other current assets
Derivatives, Fair Value [Line Items]
Derivative Asset	915	[1]
Designated as Hedging Instrument [Member] | Cash Flow Hedging [Member] | Foreign currency option contracts [Member] | Prepaid and other current assets
Derivatives, Fair Value [Line Items]
Derivative Asset	673	[1]
Designated as Hedging Instrument [Member] | Cash Flow Hedging [Member] | Foreign currency option contracts [Member] | Other current liabilities
Derivatives, Fair Value [Line Items]
Derivative Liability	(214)	[1]
Not Designated as Hedging Instrument [Member] | Foreign currency exchange contracts [Member] | Prepaid and other current assets
Derivatives, Fair Value [Line Items]
Derivative Asset	25	[1]
Not Designated as Hedging Instrument [Member] | Foreign currency option contracts [Member] | Prepaid and other current assets
Derivatives, Fair Value [Line Items]
Derivative Asset	8	[1]
Not Designated as Hedging Instrument [Member] | Interest rate swaps [Member] | Other non-current liabilities
Derivatives, Fair Value [Line Items]
Derivative Liability	(4,659)	[1]
Not Designated as Hedging Instrument [Member] | Fuel hedge contracts [Member] | Prepaid and other current assets
Derivatives, Fair Value [Line Items]
Derivative Asset	$ 160	[1]

[1] See Note 7 — Fair Value Measurements for further information on the fair value of our derivatives including their classification within the fair value hierarchy.