CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY - 3 months ended Mar. 31, 2016 - 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, 2015		48,132,223				1,357,863	200,000
BALANCE at Dec. 31, 2015	$ 466,765	$ 482	$ 589,885	$ (73,627)	$ (9,819)	$ (40,158)	$ 2
Increase (Decrease) in Shareholders' Equity [Roll Forward]
Net income	1,949			1,949
Other comprehensive income (loss)	(703)				(703)
Exercise of common stock options (in shares)		10,500
Exercise of common stock options	151	$ 0	151
Stock Issued During Period, Shares, Share-based Compensation, Net of Forfeitures		21,995
Stock Issued During Period, Value, Share-based Compensation, Net of Forfeitures	3,904	$ 1	3,903
Shares withheld for tax withholding obligations (in shares)		(39,692)
Shares withheld for employee taxes	(2,008)	$ 0	(2,008)
Issuance of common stock to Board of Directors and Scientific Advisory Board Shares		20,546
Issuance of common stock to Board of Directors and Scientific Advisory Board Value	708	$ 0	708
Issuance of common stock to employees under an Employee Stock Purchase Plan (ESPP) (in shares)		2,143
Issuance of common stock to employees under an ESPP	130	$ 0	130
BALANCE (in shares) at Mar. 31, 2016		48,147,715				1,357,863	200,000
BALANCE at Mar. 31, 2016	$ 470,896	$ 483	$ 592,769	$ (71,678)	$ (10,522)	$ (40,158)	$ 2