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DESCRIPTION OF BUSINESS (Details) $ in Millions | 1 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2016 USD ($) shares | Sep. 30, 2021 segment
Variable Interest Entity [Line Items] |  |
Number of operating segments | segment |  | 1
Viventia Bio, Inc. |  |
Variable Interest Entity [Line Items] |  |
Shares of common stock issued to the selling shareholders (in shares) | shares | 4,000,000 |
Percentage of voting interests acquired (as a percent) | 19.90% |
One-time milestone payment upon first sale of product | $ 12.5 |
Period during which quarterly earn-outs are payable after date of net sales | 15 years |
Period in which acquiree is to use commercially reasonable efforts to achieve marketing authorizations | 7 years |
Viventia Bio, Inc. | Vicinium | Collaborative Arrangement, Revenue based on Specified Milestone |  |
Variable Interest Entity [Line Items] |  |
Percentage of net sales of quarterly earn-out payments during earn-out periods | 2.00% |
Viventia Bio, Inc. | Vicinium | Europe | Collaborative Arrangement, Revenue based on Specified Milestone |  |
Variable Interest Entity [Line Items] |  |
One-time milestone payment upon first sale of product | $ 7.0 |
Viventia Bio, Inc. | Vicinium | Japan | Collaborative Arrangement, Revenue based on Specified Milestone |  |
Variable Interest Entity [Line Items] |  |
One-time milestone payment upon first sale of product | $ 3.0 |

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