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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - RESEARCH AND DEVELOPMENT (Details) | 9 Months Ended
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Sep. 30, 2019
Organization Consolidation And Presentation Of Financial Statements [Abstract] |
Percentage of costs to be paid by Geron after termination of Collaboration Agreement | 100.00%

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- Definition Represents the percentage of costs that the company must pay after the termination of the Collaboration Agreement. + References No definition available. + Details
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