Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012
Consolidated Statements of Comprehensive Income
Net income	$ 37,520	$ 32,927
Other comprehensive income (loss):
Change in fair value of derivative instruments designated as cash flow hedges (net of income tax effect of $(875) and $0, respectively)	(1,601)
Amortization of loss on terminated derivative instruments designated as cash flow hedges (net of income tax effect of $277 and $282, respectively)	506	518
Foreign currency translation adjustment	(346)	108
Other comprehensive (loss) income, net of tax	(1,441)	626
Comprehensive income	$ 36,079	$ 33,553

The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the reporting entity. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, but excludes any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

+ References+ Details

Net of tax amount of other comprehensive income (loss) attributable to the parent entity.

+ References

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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).

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+ Details