Annual report pursuant to Section 13 and 15(d)

Financial Instruments and Risk Management (Gross Notional Amount of Outstanding Derivatives) (Details)

v3.3.1.900
Financial Instruments and Risk Management (Gross Notional Amount of Outstanding Derivatives) (Details) - Foreign Exchange Forward [Member] - USD ($)
$ in Thousands
Dec. 31, 2015
Dec. 31, 2014
Designated as Hedging Instrument [Member]    
Derivatives, Fair Value [Line Items]    
Currency forward contracts $ 161,000 $ 103,000
Not Designated as Hedging Instrument [Member]    
Derivatives, Fair Value [Line Items]    
Currency forward contracts $ 113,195 $ 128,000