Acquisition of Proteolix (Details) (Proteolix, USD $) In Millions, unless otherwise specified	1 Months Ended
Sep. 30, 2012	Apr. 30, 2010	Nov. 16, 2009
Proteolix
Acquisition of Proteolix disclosures
Cash consideration paid for acquisition			$ 276.0
Amount of cash consideration paid for acquisition of Proteolix held in escrow account			27.6
Contingent consideration payment	80.0	40.0
Portion of contingent consideration payment held in escrow account		4.0
Number of days after completion of enrollment earn-out payment made		180 days
Potential contingent consideration payment	$ 365.0

Represents the portion of cash paid for the acquisition that was held in escrow.

No definition available.

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- Definition

Contingent consideration payment made related to achievement of development milestone.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Period of time after completion of enrollment in a clinical trial that triggered payment of the contingent consideration.

+ References

No definition available.

+ Details

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- Definition

Represents the portion of cash paid for the acquisition contingent consideration that was held in escrow.

+ References

No definition available.

+ Details

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- Definition

Amount of potential cash payments that could result from the contingent consideration arrangement.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 51

-Subparagraph f

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Amount of cash paid to acquire the entity.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141R

-Paragraph 68

-Subparagraph f(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.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 51

-Subparagraph d

-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.

+ Details

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- Details

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