Condensed Consolidated Statements of Comprehensive Income (Loss) (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Statement of Comprehensive Income [Abstract]
Net income (loss) :	$ 6,058	$ (6,170)	$ 11,137	$ 438
Unrealized net gain/(loss) on available-for-sale securities, net of tax	90	539	24	(559)
Less: Reclassification of net realized (gain)/loss included in net income, net of tax	(136)	(364)	292	(600)
Comprehensive income (loss)	$ 6,012	$ (5,995)	$ 11,453	$ (721)