Derivative Instruments and Hedging Activities - Open Foreign Currency Contracts (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Derivative [Line Items]
Derivative, Fair Value, Net	$ (1,796)	$ (2,741)
Cash Flow Hedging | Foreign exchange contracts
Derivative [Line Items]
Notional Amounts (in US Dollars)	144,184
Derivative, Fair Value, Net	(841)
Cash Flow Hedging | Foreign exchange contracts | Currency, Australian Dollar
Derivative [Line Items]
Notional Amounts (in US Dollars)	8,542
Derivative, Fair Value, Net	(146)
Cash Flow Hedging | Foreign exchange contracts | Currency, Canadian Dollar
Derivative [Line Items]
Notional Amounts (in US Dollars)	79,362
Derivative, Fair Value, Net	1,041
Cash Flow Hedging | Foreign exchange contracts | Currency Euro [Member]
Derivative [Line Items]
Notional Amounts (in US Dollars)	1,228
Derivative, Fair Value, Net	(51)
Cash Flow Hedging | Foreign exchange contracts | Currency, Swedish Krone
Derivative [Line Items]
Notional Amounts (in US Dollars)	10,182
Derivative, Fair Value, Net	(15)
Cash Flow Hedging | Foreign exchange contracts | Currency, Japanese Yen
Derivative [Line Items]
Notional Amounts (in US Dollars)	38,426
Derivative, Fair Value, Net	(2,477)
Cash Flow Hedging | Foreign exchange contracts | Currency, Mexican Peso
Derivative [Line Items]
Notional Amounts (in US Dollars)	6,444
Derivative, Fair Value, Net	$ 807