Derivative Instruments (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Derivative Instruments
Forward contracts, designated as cash flow hedges, fair value liabilities	$ (6,018)
Forward contracts, designated as cash flow hedges, fair value assets		5,105
Total derivatives designated as cash flow hedging instruments	(6,018)	5,105
Cash flow hedge gain (loss) recognized in accumulated other comprehensive loss associated with foreign exchange rate forward contracts	$ 538	$ (287)

Accumulated adjustment, net of tax, that results from the process of translating subsidiary financial statements and foreign equity investments into the reporting currency from the functional currency of the reporting entity, net of reclassification of realized foreign currency translation gains or losses.

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+ Details