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Nature of Business - Additional Information (Detail) - USD ($) $ in Thousands | 3 Months Ended |
--- | --- | ---
Mar. 31, 2019 | Dec. 31, 2018
Nature Of Business And Basis Of Presentation [Line Items] |  |
Percentage of Ownership before transaction | 10.00% |
Termination fees | $ 700 |
Liabilities obligation, termination fee | $ 300 |
Transfer of shares restriction period | 180 days |
Accumulated deficit | $ (226,245) | $ (216,830)
Ocugen [Member] |  |
Nature Of Business And Basis Of Presentation [Line Items] |  |
Percentage of Ownership before transaction | 90.00% |
Termination fees | $ 600 |
Voting Agreement [Member] |  |
Nature Of Business And Basis Of Presentation [Line Items] |  |
Percentage of Voting Interests Acquired | 68.00% |
Maximum [Member] |  |
Nature Of Business And Basis Of Presentation [Line Items] |  |
Percentage of Ownership before transaction | 5.00% |

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