CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Statement of Comprehensive Income [Abstract]
Net income	$ 249,104	$ 61,102	$ 126,172
Other comprehensive income (loss):
Unrealized (loss) gain on available for sale securities, net of tax	(202)	316	(114,283)
Cumulative translation adjustment, net of tax	(1,581)	416	1,365
Comprehensive income	$ 247,321	$ 61,834	$ 13,254