Financial Instruments (Details) In Thousands, unless otherwise specified	Jun. 30, 2013 Designated as Hedging Instrument [Member] USD ($)	Dec. 31, 2012 Designated as Hedging Instrument [Member] USD ($)	Jun. 30, 2013 Not Designated as Hedging Instrument [Member] USD ($)	Jun. 30, 2013 Cross Currency Interest Rate Contract [Member] Designated as Hedging Instrument [Member] USD ($)	Jun. 30, 2013 Cross Currency Interest Rate Contract [Member] Designated as Hedging Instrument [Member] CHF	Jun. 30, 2013 Cross Currency Interest Rate Contract [Member] Designated as Hedging Instrument [Member] Other Liabilities [Member] USD ($)	Dec. 31, 2012 Cross Currency Interest Rate Contract [Member] Designated as Hedging Instrument [Member] Other Liabilities [Member] USD ($)	Jun. 30, 2013 Foreign Exchange Forward [Member] Designated as Hedging Instrument [Member] Prepaid and Other Current Assets [Member] USD ($)	Dec. 31, 2012 Foreign Exchange Forward [Member] Designated as Hedging Instrument [Member] Prepaid and Other Current Assets [Member] USD ($)	Jun. 30, 2013 Foreign Exchange Forward [Member] Designated as Hedging Instrument [Member] Other Accrued Expenses [Member] USD ($)	Dec. 31, 2012 Foreign Exchange Forward [Member] Designated as Hedging Instrument [Member] Other Accrued Expenses [Member] USD ($)
Derivatives, Fair Value [Line Items]
Notional amount of forward contracts	$ 66,791	$ 9,090	$ 71,573
Notional amount of cross currency swap				50,000	65,100
Fair Value - Asset								1,057	85
Fair Value - Liability						$ 19,831	$ 22,681			$ 272	$ 799