Out-License of Zevalin in Certain Ex-U.S. Territories (Details) $ in Millions	Nov. 16, 2015 USD ($)
Mundipharma [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Proceeds from sale of Spectrum GK	$ 2.2
ZEVALIN Ex-U.S. Distribution Rights [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Potential payment	2.0
Payment One [Member] \| ZEVALIN Ex-U.S. Distribution Rights [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Total consideration received	15.0
Payment Two [Member] \| ZEVALIN Ex-U.S. Distribution Rights [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Total consideration received	3.0
Total Consideration [Member] \| ZEVALIN Ex-U.S. Distribution Rights [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Total consideration received	$ 18.0

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Topic 230
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