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ORGANIZATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) | 12 Months Ended
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Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012
Net Loss Per Share |  |  |
Potential dilutive securities excluded from diluted earnings (loss) per share calculation (in shares) | 3,072,340us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount | 532,120us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount | 11,497us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount
Minimum |  |  |
Marketable securities |  |  |
Original maturity period of marketable securities | 4 months |  |
Maximum |  |  |
Marketable securities |  |  |
Original maturity period of marketable securities | 19 months |  |

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