Consolidated Statements of Shareholders' Equity (Unaudited) - 6 months ended Jun. 30, 2016 - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock [Member]	Treasury Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Loss [Member]
Balance at Dec. 31, 2015	$ 177,277	$ 100	$ (73)	$ 363,280	$ (182,864)	$ (3,166)
Balance, Shares at Dec. 31, 2015		100,180	(31)
Stock-based compensation	2,477			2,477
Issuance of common stock, net of issuance costs	57,637	$ 15		57,622
Issuance of common stock, net of issuance costs, Shares		14,474
Exercise of stock options and restricted stock units	165			165
Exercise of stock options and restricted stock units, Shares		346
Return of common stock to pay withholding taxes on restricted stock	(130)		$ (130)
Return of common stock to pay withholding taxes on restricted stock, Shares			(41)
Other comprehensive gain	1,510					1,510
Net loss	(93,044)				(93,044)
Balance at Jun. 30, 2016	$ 145,892	$ 115	$ (203)	$ 423,544	$ (275,908)	$ (1,656)
Balance, Shares at Jun. 30, 2016		115,000	(72)