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Equity Financings and Warrants (Details) (USD $) | 12 Months Ended | 132 Months Ended |  | 1 Months Ended | 12 Months Ended | 1 Months Ended | 12 Months Ended | 1 Months Ended |  |  | 1 Months Ended
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Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2012 | Dec. 31, 2012 Warrant [Member] | Dec. 31, 2012 Maximum [Member] Warrant [Member] | Dec. 31, 2012 Minimum [Member] Warrant [Member] | Jan. 22, 2013 PIPE Transaction [Member] 2013 Equity Financings [Member] | Jan. 22, 2013 PIPE Transaction [Member] 2013 Equity Financings [Member] Warrant [Member] | Dec. 18, 2012 PIPE Transaction [Member] 2012 Equity Financings [Member] | Oct. 22, 2012 PIPE Transaction [Member] 2012 Equity Financings [Member] | Dec. 18, 2012 PIPE Transaction [Member] 2012 Equity Financings [Member] Warrant [Member] | Oct. 22, 2012 PIPE Transaction [Member] 2012 Equity Financings [Member] Warrant [Member] | Dec. 21, 2011 PIPE Transaction [Member] 2011 Equity Financings [Member] | Dec. 31, 2012 PIPE Transaction [Member] 2011 Equity Financings [Member] | Dec. 21, 2011 PIPE Transaction [Member] 2011 Equity Financings [Member] Warrant [Member] | Jan. 31, 2013 Registered Direct Offering [Member] 2013 Equity Financings [Member] | Jan. 31, 2013 Registered Direct Offering [Member] 2013 Equity Financings [Member] Warrant [Member] | Aug. 02, 2012 Registered Direct Offering [Member] 2012 Equity Financings [Member] | Dec. 31, 2012 Registered Direct Offering [Member] 2012 Equity Financings [Member] | Aug. 02, 2012 Registered Direct Offering [Member] 2012 Equity Financings [Member] Warrant [Member] | Jan. 31, 2013 Registered Direct Offering [Member] 2011 Equity Financings [Member] | Apr. 18, 2011 Registered Direct Offering [Member] 2011 Equity Financings [Member] | Dec. 31, 2012 Registered Direct Offering [Member] 2011 Equity Financings [Member] | Apr. 15, 2011 Registered Direct Offering [Member] 2011 Equity Financings [Member] | Apr. 18, 2011 Registered Direct Offering [Member] 2011 Equity Financings [Member] Warrant [Member]
Equity financings and warrants (Textual) [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate common stock sold | 2,660,315 | 2,030,500 | 2,660,315 |  |  |  | 356,430 |  | 86,186 | 137,530 |  |  | 277,778 |  |  | 164,636 |  | 406,099 |  |  |  | 280,112 |  |  |
Additional shares purchased | 315,356 |  | 315,356 |  |  |  | 249,501 |  | 64,640 | 103,148 |  |  | 208,333 |  |  | 65,855 |  | 304,575 |  |  |  | 196,079 |  |  |
Aggregate gross proceeds |  |  |  |  |  |  | $ 1,000,000 |  | $ 250,000 | $ 325,000 |  |  | $ 1,750,000 |  |  | $ 730,000 |  | $ 953,000 |  |  |  | $ 3,000,000 |  |  |
Proceeds from the issuance of common stock | 1,528,000 | 4,726,000 | 14,109,000 |  |  |  | 850,000 |  | 230,000 | 280,000 |  |  | 1,500,000 |  |  | 630,000 |  | 741,000 |  |  |  | 2,500,000 |  |  |
Registered Direct Offering Close Date |  |  |  |  |  |  |  |  |  |  |  |  | Apr. 21, 2011 |  |  |  |  | Aug. 08, 2011 |  |  | Feb. 04, 2013 |  |  |  |
Public Equity Offering Close Date |  |  |  |  |  |  | Jan. 25, 2013 |  | Dec. 20, 2012 | Oct. 25, 2012 |  |  |  |  |  |  |  |  |  |  |  |  | Dec. 21, 2011 |  |
Shares of common stock purchased |  |  |  |  |  |  |  | 0.70 |  |  | 0.75 | 0.75 |  |  | 0.75 |  | 0.40 |  |  | 0.75 |  |  |  |  | 0.70
Purchase price for common stock unit |  |  |  |  |  |  | 2.81 |  | 2.90 | 2.36 |  |  | 6.30 |  |  | 4.43 |  | 2.35 |  |  |  | 10.71 |  |  |
Warrants were exercisable upon issuance, expiry year |  |  |  |  |  |  | 7 years |  | 5 years | 5 years |  |  | 5 years |  |  | 5 years |  | 6 years |  |  |  | 5 years |  |  |
Closing bid price of the common stock |  |  |  |  |  |  | 100.00% |  | 100.00% |  |  |  | 110.00% |  |  |  |  |  |  |  |  |  |  | 120.00% |
Number of warrants outstanding |  |  |  | 930,725 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Warrant price per share |  |  |  | 9.10 | 116.89 | 1.80 | 2.28 |  | 2.34 | 1.80 |  |  | 8.91 |  |  | 4.13 |  | 2.76 |  |  |  |  |  | 15.12 |
Exercisable period of warrants |  |  |  |  |  |  |  |  |  |  |  |  | 6 months |  |  |  |  |  | 6 months |  |  |  |  |  |
Additional Cost Related To Registration Statement |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 61,000 |  |  |  |  |  |  |  |  |  |  |

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