Condensed Consolidated Statements of Comprehensive Income (unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Comprehensive income, net of taxes
Net income	$ 4,147us-gaap_NetIncomeLoss	$ 18,275us-gaap_NetIncomeLoss
Change in unrealized gain (loss) on marketable securities	6	(1)
Comprehensive income, net of tax	$ 4,153us-gaap_ComprehensiveIncomeNetOfTax	$ 18,274us-gaap_ComprehensiveIncomeNetOfTax

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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