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Collaborative and Other Relationships - OCREVUS (Details) - USD ($) $ in Millions | 1 Months Ended | 3 Months Ended
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Mar. 31, 2017 | Mar. 31, 2024
OCREVUS |  |
Collaborative arrangements and non-collaborative arrangement transactions |  |
Royalty operating profit threshold for highest royalty rate percentage | $ 900.0 |
Reduction in royalty rate | 50.00% |
Collaboration agreement term | 11 years |
OCREVUS | Foreign Tax Authority |  |
Collaborative arrangements and non-collaborative arrangement transactions |  |
Royalty percentage to be received | 3.00% |
OCREVUS | Minimum |  |
Collaborative arrangements and non-collaborative arrangement transactions |  |
Royalty percentage to be received | 13.50% |
OCREVUS | Maximum |  |
Collaborative arrangements and non-collaborative arrangement transactions |  |
Royalty percentage to be received | 24.00% |
Mosunetuzumab |  |
Collaborative arrangements and non-collaborative arrangement transactions |  |
Percentage of future development costs |  | 30.00%

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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. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 808 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479402/808-10-50-1 + Details
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