Condensed Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Condensed Consolidated Statements of Comprehensive Income
Net (loss) income	$ (12,180)	$ 66,667	$ 53,091	$ 145,286
Other comprehensive (loss) income, net of tax:
Foreign currency translation adjustment during the period	(608)	(455)	(999)	(167)
Change in fair value of corporate debt securities
Unrealized holding gains (losses) on corporate debt securities arising during the period		155	(98)	85
Less: Reclassification adjustments for gains included in net income	(1,296)		(1,296)
Change in fair value of corporate debt securities, net	(1,296)	155	(1,394)	85
Other comprehensive loss	(1,904)	(300)	(2,393)	(82)
Comprehensive (loss) income	$ (14,084)	$ 66,367	$ 50,698	$ 145,204

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 economic entity, including both controlling (parent) and noncontrolling interests. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, including any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

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