CONSOLIDATED STATEMENT OF SHAREHOLDERS' EQUITY (USD $) In Thousands, except Share data, unless otherwise specified	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 at Dec. 31, 2013	$ 427,686	$ 468	$ 572,401	$ (130,159)	$ (4,368)	$ (10,658)	$ 2
BALANCE (in shares) at Dec. 31, 2013		46,825,168				401,501	200,000
Increase (Decrease) in Shareholders' Equity [Roll Forward]
Net income	28,728			28,728
Other comprehensive income	295				295
Repurchase of common stock, shares						714,328
Repurchase of common stock	(22,500)					(22,500)
Exercise of common stock options, shares		76,883
Exercise of common stock options	1,001	1	1,000
Issuance of common stock to employees, shares		83,334
Issuance of common stock to employees	6,079	1	6,078
Shares withheld for employee taxes, shares		(83,665)
Shares withheld for employee taxes	(2,840)	(1)	(2,839)
Issuance of common stock to Board of Directors and Scientific Advisory Board Shares		33,234
Issuance of common stock to Board of Directors and Scientific Advisory Board Value	1,052	0	1,052
Issuance of common stock to employees under an Employee Stock Purchase Plan (ESPP) (in shares)		9,162
Issuance of common stock to employees under an ESPP	279	0	279
BALANCE at Sep. 30, 2014	$ 439,780	$ 469	$ 577,971	$ (101,431)	$ (4,073)	$ (33,158)	$ 2
BALANCE (in shares) at Sep. 30, 2014		46,944,116				1,115,829	200,000