The assumptions made for purposes of estimating fair value (Details)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
The assumptions made for purposes of estimating fair value
Divident yield:	0.00%	0.00%	0.00%
Expected term of options (years):	6	6	6
Risk free interest rate:(Minimum)	0.93%	0.80%	1.16%
Risk free interest rate:(Maximum)	1.70%	1.16%	2.61%
Volatility:(Minimum)	92.00%	80.00%	74.00%
Volatility:(Maximum)	107.00%		79.00%