Derivative Instruments and Hedging Activities (Details)
In Thousands, unless otherwise specified
3 Months Ended
Mar. 31, 2015
derivative
Dec. 31, 2014
derivative
Mar. 31, 2015
6 3/4% Notes
Net Investment Hedging [Member]
Designated as Hedging Instrument [Member]
USD ($)
Mar. 31, 2015
6 3/4% Notes
Net Investment Hedging [Member]
Designated as Hedging Instrument [Member]
EUR (€)
Mar. 31, 2014
6 3/4% Notes
Net Investment Hedging [Member]
Designated as Hedging Instrument [Member]
EUR (€)
Mar. 31, 2015
Foreign exchange contracts
USD ($)
Mar. 31, 2014
Foreign exchange contracts
USD ($)
Mar. 31, 2015
Forward contracts
Purchases
Euros : U.S. dollars
EUR (€)
Mar. 31, 2015
Forward contracts
Sales
Euros : U.S. dollars
USD ($)
Derivative instruments                  
Targeted percentage of debt portfolio to be fixed with interest rates 75.00%                
Number of derivative instrument with contingent features of credit risk 0 0              
Notional amount of derivatives       € 36,000 € 64,208     € 206,000 $ 229,845
Net cash payments from foreign currency forward contracts           16,820 7,199    
Derivatives used in Net Investment Hedge, Net of Tax     $ 18,742