CONSOLIDATED STATEMENT OF SHAREHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Loss [Member]	Treasury Stock [Member]	Series A Nonconvertible Preferred Stock [Member] Preferred Stock [Member]
BALANCE at Dec. 31, 2014					$ (4,382)
Net income (loss)	$ (3,410)
Other comprehensive income	704
BALANCE at Sep. 30, 2015					(3,678)
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
Net income (loss)	22,251			22,251
Other comprehensive income	232				232
Exercise of common stock options (in shares)		12,500
Exercise of common stock options	182		182
Issuance of common stock to employees (in shares)		219,173
Issuance of common stock to employees	9,245	$ 2	9,243
Shares withheld for employee taxes (in shares)		(91,659)
Shares withheld for employee taxes	(4,840)	$ (1)	(4,839)
Issuance of common stock to Board of Directors and Scientific Advisory Board (in shares)		35,546
Issuance of common stock to Board of Directors and Scientific Advisory Board	1,570		1,570
Issuance of common stock to employees under an ESPP (in shares)		6,808
Issuance of common stock to employees under an ESPP	412		412
BALANCE (in shares) at Sep. 30, 2016		48,314,591				1,357,863	200,000
BALANCE at Sep. 30, 2016	$ 495,817	$ 483	$ 596,453	$ (51,376)	$ (9,587)	$ (40,158)	$ 2