Fair Value of Assets and Liabilities (Details 1) (USD $)	3 Months Ended	12 Months Ended
Mar. 31, 2012	Dec. 31, 2011
Assumptions and other inputs used to compute the fair value of the warrant liability
Common stock price	$ 1.73	$ 1.05
Expected warrant exercise price	$ 1.63	$ 1.46
Remaining term of warrant (years)	4 years 7 months 6 days	4 years 9 months 18 days
Expected volatility	61.00%	58.00%
Average risk free interest rate	0.90%	0.80%
Expected dividend yield
Expected percentage of warrants to be exercised	100.00%	100.00%

Fair value assumptions expected percentage of warrants to be exercised.

No definition available.

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- Details

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- Definition

Agreed upon price for the exchange of the underlying asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258

+ Details

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- Definition

Expected dividends to be paid to holders of the underlying shares or financial instruments (expressed as a percentage of the share or instrument's price).

+ References

+ Details

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- Definition

Period the instrument, asset or liability is expected to be outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

+ Details

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- Definition

Measure of dispersion, in percentage terms (for instance, the standard deviation or variance), for a given stock price.

+ References

+ Details

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- Definition

Risk-free interest rate assumption used in valuing an instrument.

+ References

+ Details

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- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

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