Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Consolidated Statements of Comprehensive Income
Net income (loss)	$ 3,916	$ (2,371)	$ 7,092	$ (14,713)
Other comprehensive (loss) income:
Unrealized net gain (loss) on marketable securities	44	(36)	47	(35)
Other comprehensive income (loss):	44	(36)	47	(35)
Comprehensive income (loss)	$ 3,960	$ (2,407)	$ 7,139	$ (14,748)