Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Consolidated Statements of Comprehensive Income (Loss)
Net income (loss)	$ 14,016	$ 19,871	$ (92,273)
Other comprehensive (loss) income:
Unrealized net (loss) gain on marketable securities	(334)	(154)	57
Other comprehensive (loss) income:	(334)	(154)	57
Comprehensive income (loss)	$ 13,682	$ 19,717	$ (92,216)