Annual report pursuant to Section 13 and 15(d)

Financial Instruments and Risk Management (Balance Sheet Classification and Fair Value of Derivative Instruments) (Details)

v3.3.1.900
Financial Instruments and Risk Management (Balance Sheet Classification and Fair Value of Derivative Instruments) (Details) - Forward Contracts [Member] - USD ($)
$ in Thousands
Dec. 31, 2015
Dec. 31, 2014
Not Designated as Hedging Instrument [Member] | Prepaid Expenses And Other Current Assets [Member]    
Derivatives, Fair Value [Line Items]    
Fair value of derivative assets $ 1,328 $ 2,754
Not Designated as Hedging Instrument [Member] | Accrued Liabilities [Member]    
Derivatives, Fair Value [Line Items]    
Fair value of derivative liabilities 1,693 924
Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] | Prepaid Expenses And Other Current Assets [Member]    
Derivatives, Fair Value [Line Items]    
Fair value of derivative assets 5,394 9,993
Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] | Other Noncurrent Assets [Member]    
Derivatives, Fair Value [Line Items]    
Fair value of derivative assets 566 0
Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] | Accrued Liabilities [Member]    
Derivatives, Fair Value [Line Items]    
Fair value of derivative liabilities $ 224 $ 0