CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Statement of Comprehensive Income [Abstract]
Net income	$ 13,787us-gaap_NetIncomeLoss	$ 9,564us-gaap_NetIncomeLoss
Other comprehensive income:
Unrealized gain (loss) on available-for-sale securities, net of tax	2	(3)
Comprehensive income	$ 13,789	$ 9,561

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

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