CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY - 6 months ended Jun. 30, 2015 - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Income Loss [Member]	Treasury Stock [Member]	Series A Nonconvertible Preferred Stock [Member] Preferred Stock [Member]
BALANCE (in shares) at Dec. 31, 2014		47,061,826				1,357,863	200,000
BALANCE at Dec. 31, 2014	$ 448,742	$ 471	$ 581,114	$ (88,305)	$ (4,382)	$ (40,158)	$ 2
Increase (Decrease) in Shareholders' Equity [Roll Forward]
Net loss	(10,457)			(10,457)
Other comprehensive income	424				424
Exercise of common stock options, shares		191,640
Exercise of common stock options	1,372	$ 2	1,370
Issuance of common stock to employees, shares		292,575
Issuance of common stock to employees	4,959	$ 3	4,956
Shares withheld for employee taxes, shares		(123,492)
Shares withheld for employee taxes	(5,280)	$ (1)	(5,279)
Issuance of common stock to Board of Directors and Scientific Advisory Board Shares		29,351
Issuance of common stock to Board of Directors and Scientific Advisory Board Value	959	$ 0	959
Issuance of common stock to employees under an Employee Stock Purchase Plan (ESPP) (in shares)		5,819
Issuance of common stock to employees under an ESPP	218	$ 0	218
BALANCE (in shares) at Jun. 30, 2015		47,457,719				1,357,863	200,000
BALANCE at Jun. 30, 2015	$ 440,937	$ 475	$ 583,338	$ (98,762)	$ (3,958)	$ (40,158)	$ 2