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ORGANIZATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - CONCENTRATIONS OF CUSTOMERS AND SUPPLIERS (Details) - customer | 12 Months Ended
--- | ---
Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
Concentration risk |  |  |
Number of customers |  | 2 | 2
Concentrations of Customers and Suppliers |  |  |
Concentration risk |  |  |
Concentration risk percentage |  | 31.00% | 42.00%
Janssen Biotech |  |  |
Concentration risk |  |  |
Concentration risk percentage | 96.00% |  |

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