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COMMITMENTS AND CONTINGENCIES, Royalty Agreements (Details) | Mar. 22, 2021 | Jun. 22, 2018 | May 01, 2012
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Investor Royalty Agreement [Member] |  |  |
Royalty Agreements [Abstract] |  |  |
Percentage of royalty receive equal to revenues from sale of business | 4.00% |  |
Percentage of payment of additional royalty on gross sales |  |  | 1.00%
Collaborator Royalty Agreement [Member] |  |  |
Royalty Agreements [Abstract] |  |  |
Percentage of royalty receive equal to revenues from sale of business |  | 6.00% |

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- Definition Percentage of additional royalty payable on gross sales by the entity. + References No definition available. + Details
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- Definition Percentage of royalty receive equal to revenues generated from disposition of business. + References No definition available. + Details
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Namespace Prefix: | erna_
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- References No definition available. + Details
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- Details
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X
- Details
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Namespace Prefix: |
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Balance Type: |
Period Type: |