Stock Based Compensation (Tables)

12 Months Ended

Dec. 31, 2012

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]

	2012	2011	2010
Expected dividend yield	0%	0%	0%
Risk-free interest rate	1.72%	1.42%	1.57%
Expected volatility	119%	97%	107%
Expected option life (in years)	9.70	4.68	3.27

Schedule of Share-based Compensation, Stock Options, Activity [Table Text Block]

				Weighted-
			Weighted	Average
			Average	Remaining	Aggregate
	Number of		Exercise	Contractual	Intrinsic
	Options		Price	Term (years)	Value
			$		$
Outstanding, December 31, 2009	5,949,700		1.88
Granted	1,240,000		1.46
Exercised	(454,100	)	0.95
Outstanding, December 31, 2010	6,735,600		1.86
Granted	3,427,000		2.88
Exercised	(2,223,920	)	1.01
Expired	(187,500	)	2.59
Outstanding, December 31, 2011	7,751,180		2.54
Granted	1,690,500		1.32
Exercised	(120,800	)	0.80
Expired	(95,000	)	3.13
Outstanding, December 31, 2012	9,225,880		2.33	6.39	615,497
Exercisable, December 31, 2012	8,018,830		2.47	5.92	547,856

Schedule of Share-based Compensation, Non-vested Stock Options, Activity [Table Text Block]

			Weighted
			Average
	Number of		Grant Date
Non-vested stock options	Options		Fair Value
			$
Non-vested at December 31, 2009	127,000		1.33
Granted	1,240,000		0.93
Vested	(1,292,000	)	0.95
Non-vested at December 31, 2010	75,000		1.16
Granted	3,427,000		2.05
Vested	(3,020,500	)	2.13
Non-vested at December 31, 2011	481,500		1.37
Granted	1,690,500		1.23
Vested	(964,950	)	1.20
Non-vested at December 31, 2012	1,207,050		1.24