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Legal Proceedings, Commitments and Contingencies - Additional Information (Details) $ in Millions | Jun. 30, 2017 USD ($)
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Commitments And Contingencies Disclosure [Abstract] |
Estimate of milestone payments | $ 15.5

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- References No definition available. + Details
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- Definition Reflects estimated obligations that are due and payable upon achievement of certain criteria categorized as developmental, regulatory, or commercial milestones. + References No definition available. + Details
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Namespace Prefix: | xoma_
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