Accumulated Other Comprehensive Income (Loss) (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Activity in other comprehensive income (loss) related to forward exchange contracts held
Change in fair value of forward exchange contracts, net of tax	$ (2,474)	$ 2,031	$ 3,149	$ (2,545)	$ 3,554
Adjustment for net gains/losses realized and included in net income	1,178	631	2,540	(5,219)	1,891
Change in unrecognized gains/losses on forward exchange contracts	$ (1,296)	$ 2,662	$ 5,689	$ (7,764)	$ 5,445

Net of tax amount of the income statement impact of the reclassification adjustment of accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges realized in net income. Also includes reclassification adjustments of an entity's share of an equity investee's deferred hedging gain (loss) realized in net income.

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+ Details

- Definition

Net of tax amount, before reclassification adjustments, of the change in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges. Also includes an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

+ References

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+ Details