Derivative Instruments and Hedging Activities (Details 1) (Foreign Exchange Contract [Member], USD $) In Thousands, unless otherwise specified			12 Months Ended							12 Months Ended
	Dec. 31, 2011 Designated as Hedging Instrument [Member]	Dec. 31, 2010 Designated as Hedging Instrument [Member]	Dec. 31, 2011 Designated as Hedging Instrument [Member] Maximum [Member]	Dec. 31, 2011 Designated as Hedging Instrument [Member] Prepaid Expenses and Other Current Assets [Member]	Dec. 31, 2010 Designated as Hedging Instrument [Member] Prepaid Expenses and Other Current Assets [Member]	Dec. 31, 2011 Designated as Hedging Instrument [Member] Accrued Expenses and Other Liabilities [Member]	Dec. 31, 2010 Designated as Hedging Instrument [Member] Accrued Expenses and Other Liabilities [Member]	Dec. 31, 2011 Not Designated as Hedging Instrument [Member]	Dec. 31, 2010 Not Designated as Hedging Instrument [Member]	Dec. 31, 2011 Not Designated as Hedging Instrument [Member] Maximum [Member]	Dec. 31, 2011 Not Designated as Hedging Instrument [Member] Prepaid Expenses and Other Current Assets [Member]	Dec. 31, 2010 Not Designated as Hedging Instrument [Member] Prepaid Expenses and Other Current Assets [Member]	Dec. 31, 2011 Not Designated as Hedging Instrument [Member] Accrued Expenses and Other Liabilities [Member]	Dec. 31, 2010 Not Designated as Hedging Instrument [Member] Accrued Expenses and Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative maturity period ( in days)			12 months							90 days
Notional amount of derivatives	$ 42,373	$ 30,701						$ 64,451	$ 68,788
Derivative, fair value, net				$ 0	$ 440	$ 4,046	$ 0				$ 0	$ 0	$ 364	$ 424