| Exclusive Channel Collaboration Agreements - Additional Information (Detail) | 12 Months Ended | 
|---|---|
| Dec. 31, 2018 | |
| Lantibiotic ECC [Member] | |
| Research and Development Arrangement, Contract to Perform for Others [Line Items] | |
| Termination notice period | 90 days | 
| Oral Mucositis ECC [Member] | |
| Research and Development Arrangement, Contract to Perform for Others [Line Items] | |
| Termination notice period | 90 days | 
| Maximum period to cure the breach | 60 days | 
| X | ||||||||||
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- Definition Maximum period allowed for licensee to cure breach once notified of such breach by licensor. No definition available. 
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| X | ||||||||||
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- Definition Notification period required to be given for voluntary termination of license agreement. No definition available. 
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| X | ||||||||||
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available. 
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| X | ||||||||||
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- Details 
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| X | ||||||||||
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- Details 
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