Unaudited Consolidated Statement of Stockholders' Equity (USD $) In Thousands, unless otherwise specified	Total	Common Stock	Treasury Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit
Beginning balance at Dec. 31, 2012	$ 154,730	$ 5	$ (3,701)	$ 195,485	$ (40)	$ (37,019)
Beginning balance, shares at Dec. 31, 2012		53,124	2,198
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	16,205					16,205
Other comprehensive loss	(144)				(144)
Issuance costs of preferred stock and detachable warrants	(200)			(200)
Stock warrants exercised	6			6
Stock warrants exercised, shares		5
Stock options exercised	2,546			2,546
Stock options exercised, shares		333
Stock surrendered for exercise of stock options	(2,418)		(2,418)
Stock surrendered for exercise of stock options, shares			165
Restricted stock granted, shares		791
Restricted stock forfeited, shares			38
Stock granted in incentive performance plan, shares		217
Treasury stock purchased	(4,860)		(4,860)
Treasury stock purchased, shares			316
Excess tax benefit related to share-based awards	432			432
Employee stock purchase plan	352			352
Employee stock purchase plan, shares			22
Stock compensation expense	5,789			5,789
Stock issued in Florida Chemical Company acquisition	52,712	1		52,711
Stock issued in Florida Chemical Company acquisition, shares		3,284
Return of borrowed shares under share lending agreement			2,440
Ending balance at Jun. 30, 2013	$ 225,150	$ 6	$ (10,979)	$ 257,121	$ (184)	$ (20,814)
Ending balance, shares at Jun. 30, 2013		57,754	5,135