Consolidated Statements of Stockholders' Equity (USD $)	Total	Common Stock	Additional Paid-in Capital	Treasury Stock	Accumulated Other Comprehensive Loss	Retained Earnings
Beginning Balance at Dec. 31, 2009	$ 117,701,196	$ 642	$ 92,839,165	$ (14,708,237)		$ 39,569,626
Beginning Balance, shares at Dec. 31, 2009		62,119,063		2,091,600
Exercise of stock options, shares		502,205
Exercise of stock options	1,001,476	5	1,001,471
Stock-based compensation	3,682,675		3,682,675
Excess tax benefit from stock-based compensation	52,147		52,147
Reversal of tax benefit from stock options forfeited	(329,143)		(329,143)
Stock option buyback	(124,230)		(124,230)
Net income (loss)	(4,384,435)					(4,384,435)
Foreign currency translation adjustments	(35,445)				(35,445)
Ending Balance at Dec. 31, 2010	117,564,241	647	97,122,085	(14,708,237)	(35,445)	35,185,191
Ending Balance, shares at Dec. 31, 2010		62,621,268		2,091,600
Exercise of stock options, shares		539,923
Exercise of stock options	1,427,418	5	1,427,413
Stock-based compensation	3,038,300		3,038,300
Excess tax benefit from stock-based compensation	9,828		9,828
Purchase of treasury stock, shares	7,464,583	(7,464,583)		7,464,583
Purchase of treasury stock	(32,498,856)			(32,498,856)
Net income (loss)	(7,039,866)					(7,039,866)
Foreign currency translation adjustments	(45,511)				(45,511)
Ending Balance at Dec. 31, 2011	82,455,554	652	101,597,626	(47,207,093)	(80,956)	28,145,325
Ending Balance, shares at Dec. 31, 2011		55,696,608		9,556,183
Exercise of stock options, shares		881,390
Exercise of stock options	1,929,308	9	1,929,299
Stock-based compensation	3,421,506		3,421,506
Excess tax benefit from stock-based compensation	4,712,962		4,712,962
Purchase of treasury stock, shares	3,800,000	(3,807,606)		3,807,606
Purchase of treasury stock	(19,995,950)			(19,995,950)
Net income (loss)	14,737,742					14,737,742
Foreign currency translation adjustments	23,924				23,924
Ending Balance at Dec. 31, 2012	$ 87,285,046	$ 661	$ 111,661,393	$ (67,203,043)	$ (57,032)	$ 42,883,067
Ending Balance, shares at Dec. 31, 2012		52,770,392		13,363,789