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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Transfer Of Shares Restriction Period

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- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

+ References

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The amount of early contract termination fees included in liabilities subject to compromise.

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The amount of other obligations included in liabilities subject to compromise.

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The cumulative amount of the reporting entity's undistributed earnings or deficit.

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- Definition

Percentage of subsidiary's or equity investee's stock owned by parent company before stock transaction.

+ References

No definition available.

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