Intangible Assets and Goodwill - Schedule of Goodwill (Detail) (As Restated [Member], USD $) In Thousands, unless otherwise specified	6 Months Ended	12 Months Ended
Jun. 30, 2013	Dec. 31, 2012
Goodwill [Line Items]
Foreign exchange translation effects	$ (70)	$ (37)
Goodwill	7,246	7,279
ZEVALIN Rights [Member]
Goodwill [Line Items]
Acquisition	2,525	2,525
Allos Therapeutics, Inc. [Member]
Goodwill [Line Items]
Acquisition	$ 4,791	$ 4,791

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

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Amount of increase (decrease) from foreign currency translation adjustments of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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