License, Clinical Trial and Sponsored Research Agreements (Details Textual) - USD ($)  | 
1 Months Ended | ||
|---|---|---|---|
Feb. 28, 2019  | 
Mar. 17, 2018  | 
Jan. 03, 2018  | 
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| City of Hope [Member] | |||
| Research And Development Expense, Sponsored Research Payment | $ 900,000 | ||
| City of Hope [Member] | Patent and Know-how Rights [Member] | |||
| Research And Development Expense, Sponsored Research Payment | $ 75,000 | ||
| Fred Hutchinson Cancer Research Center [Member] | |||
| Research And Development Expense, Sponsored Research Payment | $ 600,000 | ||
| Nationwide Children's Hospital - C134 [Member] | |||
| Payment Of Upfront Fees | $ 200,000 | ||
| Licensing Arrangements Additional Costs Incurred | $ 152,800,000 | 
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- Definition Payment of Upfront Fees No definition available. 
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- Definition The amount of research and development expense payable on achieving milestone targets. No definition available. 
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