Derivatives (Details 1) (USD $) In Thousands, unless otherwise specified	3 Months Ended										1 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2013 Designated as Hedging Instrument [Member] Cash Flow Hedging [Member]	Mar. 31, 2012 Designated as Hedging Instrument [Member] Cash Flow Hedging [Member]	Mar. 31, 2013 Designated as Hedging Instrument [Member] Cash Flow Hedging [Member] Interest Rate Contracts [Member]	Mar. 31, 2012 Designated as Hedging Instrument [Member] Cash Flow Hedging [Member] Interest Rate Contracts [Member]	Mar. 31, 2013 Designated as Hedging Instrument [Member] Cash Flow Hedging [Member] Foreign Exchange Contracts [Member]	Mar. 31, 2012 Designated as Hedging Instrument [Member] Cash Flow Hedging [Member] Foreign Exchange Contracts [Member]	Mar. 31, 2013 Not Designated as Hedging Instrument [Member] Foreign Exchange Contracts [Member]	Mar. 31, 2012 Not Designated as Hedging Instrument [Member] Foreign Exchange Contracts [Member]	Apr. 30, 2012 Interest Rate Swap [Member] Designated as Hedging Instrument [Member] Cash Flow Hedging [Member] Bank
Derivative [Line Items]
Term of interest rate derivatives											5 years
Number of banks transacted with for interest rate swap agreements (in banks)											3
Derivative amount of hedge											$ 100,000
Variable rate basis											one-month LIBOR
Fixed interest rate											1.03%
Maximum remaining maturity of foreign currency derivatives	2 years
Derivative, Net Hedge Ineffectiveness Gain (Loss)	0	0
Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income (Loss), Effective Portion, Net			427	236	156	0	271	236
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net									$ (3,906)	$ 1,057