Derivatives (Gains and Losses for Derivatives that were Not Designated as Hedging Instruments) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Derivative [Line Items]
Gain and losses for derivatives not designated as hedging instruments	$ (24)	$ 257	$ (150)
Other Income (Expense) | Currency Contracts
Derivative [Line Items]
Gain and losses for derivatives not designated as hedging instruments	$ (24)	$ 257	$ (150)