Condensed Consolidated Statements of Comprehensive Income (Loss) (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 1,437	$ 5,394	$ (3,298)	$ (5,528)
Other comprehensive income (loss)
Unrealized gain (loss) on marketable securities, net of tax expense of $0 and $263 for the three months ended September 30, 2016 and 2015, respectively, and tax benefit of $0 and $200 for the nine months ended September 30, 2016 and 2015, respectively.	413	(449)	(21)	343
Other comprehensive income (loss)	413	(449)	(21)	343
Total comprehensive income (loss)	$ 1,850	$ 4,945	$ (3,319)	$ (5,185)