Derivative Instruments and Hedging Activities Open Foreign Currency Contracts (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Mar. 31, 2014 Cash Flow Hedging [Member] Foreign Exchange Contract [Member]	Mar. 31, 2014 Cash Flow Hedging [Member] Foreign Exchange Contract [Member] Currency Swedish Krone [Member]	Mar. 31, 2014 Cash Flow Hedging [Member] Foreign Exchange Contract [Member] Currency, Australian Dollar	Mar. 31, 2014 Cash Flow Hedging [Member] Foreign Exchange Contract [Member] Currency, Canadian Dollar	Mar. 31, 2014 Cash Flow Hedging [Member] Foreign Exchange Contract [Member] Currency, Japanese Yen	Mar. 31, 2014 Cash Flow Hedging [Member] Foreign Exchange Contract [Member] Currency, Mexican Peso	Mar. 31, 2014 Cash Flow Hedging [Member] Foreign Exchange Contract [Member] Norwegian Krone
Derivative [Line Items]
Notional Amounts (in US Dollars)		$ 87,077	$ 9,230	$ 5,723	$ 26,155	$ 21,627	$ 23,401	$ 941
Derivative, Fair Value, Net	$ 21	$ 904	$ (165)	$ (86)	$ 1,399	$ (591)	$ 351	$ (4)