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DESCRIPTION OF BUSINESS (Details) - Viventia Bio Inc. shares in Millions, $ in Millions | 1 Months Ended
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Sep. 30, 2016 USD ($) shares
Variable Interest Entity [Line Items] |
Shares of common stock issued to the selling shareholders (in shares) | shares | 4.0
Percentage of voting interests acquired | 19.90%
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%
Vicinium | Collaborative Arrangement, Revenue based on Specified Milestone | United States |
Variable Interest Entity [Line Items] |
One-time milestone payment upon first sale of product | $ 12.5
Vicinium | Collaborative Arrangement, Revenue based on Specified Milestone | Europe |
Variable Interest Entity [Line Items] |
One-time milestone payment upon first sale of product | 7.0
Vicinium | Collaborative Arrangement, Revenue based on Specified Milestone | Japan |
Variable Interest Entity [Line Items] |
One-time milestone payment upon first sale of product | $ 3.0

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