Condensed Consolidated Statements of Comprehensive Income (Loss) (unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ (65,145)	$ 5,450	$ (73,783)	$ (343)
Other comprehensive gain (loss), net of tax
Unrealized gain (loss) on marketable securities	117	(78)	39	(66)
Comprehensive income (loss)	$ (65,028)	$ 5,372	$ (73,744)	$ (409)