Warrants (Schedule Of Assumptions Used In Calculating Fair Value Of Warrants) (Details) (USD $)	3 Months Ended	12 Months Ended
Mar. 31, 2015	Dec. 31, 2014
Warrants [Abstract]
Trading market prices	$ 0.73	$ 0.70
Estimated future volatility	107.00%	108.00%
Estimated future risk-free rate, minimum	0.56%	0.74%
Estimated future risk-free rate, maximum	1.68%	1.90%
Equivalent volatility, minimum	51.00%	65.00%
Equivalent volatility, maximum	76.00%	78.00%
Equivalent risk-free rate, minimum	0.16%	0.18%
Equivalent risk-free rate, maximum	0.50%	0.63%

Investment Warrants, Fair Value Assumptions, Equivalent Risk Free Rate, Maximum

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Investment Warrants, Fair Value Assumptions, Equivalent Volatility, Minimum

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Investment Warrants, Fair Value Assumptions, Risk Free Interest Rate, Maximum

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Investment Warrants, Fair Value Assumptions, Trading Market Prices

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