Fair Value Measurements (Details 2) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Assumptions used to estimate fair value
Warrant liability		$ 1,192,000us-gaap_WarrantsAndRightsOutstanding
Estimated fair value (in dollars per share)	$ 8us-gaap_SharePrice
Series B warrants
Assumptions used to estimate fair value
Warrant liability	$ 0
Warrants \| Minimum
Assumptions used to estimate fair value
Expected volatility rate (as a percent)	75.00%
Estimated fair value (in dollars per share)	$ 0.63
Estimated time to liquidity	2 months 12 days
Warrants \| Maximum
Assumptions used to estimate fair value
Expected volatility rate (as a percent)	80.00%
Estimated fair value (in dollars per share)	$ 1.51
Estimated time to liquidity	4 years

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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

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=36462937&loc=d3e19207-110258

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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

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

+ References

No definition available.

+ Details

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- Definition

Value of outstanding derivative securities that permit the holder the right to purchase securities (usually equity) from the issuer at a specified price.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(i))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph i

-Article 4

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