Basis of Presentation (Details) (USD $)	3 Months Ended	9 Months Ended
Sep. 30, 2012	Sep. 30, 2012 item
Basis of Presentation
Number of Operating Segments		1
Product Revenue
Deferred revenue related to Kyprolis	$ 5,129,000	$ 5,129,000
Revenue reserve for Kyprolis
Provision related to current period sales	3,771,000
Credits/ Payments	(802,000)
Balance at the end of the period	2,969,000	2,969,000
Kyprolis
Product Revenue
Deferred revenue related to Kyprolis	5,100,000	5,100,000
Intangible Assets - Finite lived
Acquired IPR&D	267,300,000	267,300,000
Estimated useful life		13 years
Accumulated amortization	4,100,000	4,100,000
Kyprolis \| Chargebacks, Rebates and Other
Revenue reserve for Kyprolis
Provision related to current period sales	2,785,000
Credits/ Payments	(728,000)
Balance at the end of the period	2,057,000	2,057,000
Kyprolis \| Distribution Fees and Returns
Revenue reserve for Kyprolis
Provision related to current period sales	986,000
Credits/ Payments	(74,000)
Balance at the end of the period	$ 912,000	$ 912,000

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Represents the amount of product revenue reserve as of the balance sheet date. The entity reflects these reserves as either a reduction in the related accounts receivable from the distributor or as an accrued liability depending on the nature of sales deduction.

+ References

No definition available.

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- Definition

Represents the amount of current year payments or credits related to product revenue reserve.

+ References

No definition available.

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- Definition

Represents the amount of current year provision related to product revenue reserve.

+ References

No definition available.

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- Definition

The carrying amount of consideration received or receivable as of the balance sheet date on potential earnings that were not recognized as revenue in conformity with GAAP, and which are expected to be recognized as such within one year or the normal operating cycle, if longer, including sales, license fees, and royalties, but excluding interest income.

+ References

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

-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 43

-Section A

-Paragraph 7, 8

-Chapter 3

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 605

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 13.A.4(a).Q1)

-URI http://asc.fasb.org/extlink&oid=6600647&loc=d3e214044-122780

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section 45

-Paragraph 8

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6361293&loc=d3e6935-107765

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 13

-Section A

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- Definition

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=7658586&loc=d3e16323-109275

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 142

-Paragraph 45

-Subparagraph a(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

+ References

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