Equity method investment additional fund committed by entities.

No definition available.

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- Definition

Equity method investment amounts to correct immaterial error from prior period.

+ References

No definition available.

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- Definition

Equity Method Investment Difference Between Carrying Amount And Underlying Equity Amortization

+ References

No definition available.

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- Definition

Equity Method Investment Number Of Shares Sold

+ References

No definition available.

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- Definition

Equity Method Investments Available for Sale Carrying Amount

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No definition available.

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- Definition

Funded Investment Commitments

+ References

No definition available.

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- Definition

This is the funding commitment received in respect of the Collaboration.

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No definition available.

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- Definition

Impairment Of Equity Method Investments

+ References

No definition available.

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- Definition

Income Loss HLBV Claim On Underlying Equity Of Investee.

+ References

No definition available.

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- Definition

Losses And Distributions In Excess Of Investment

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No definition available.

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- Definition

Percentage Of Equity Interest Sold

+ References

No definition available.

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- Definition

Ordinary shares received from divesture of businesses

+ References

No definition available.

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- Definition

Unspent Funding Commitment Other

+ References

No definition available.

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- Definition

Difference between amount at which an investment accounted for under the equity method of accounting is carried (reported) on the balance sheet and amount of underlying equity in net assets the reporting Entity has in the investee.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)(3)

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-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 18

-Paragraph 20

-Subparagraph a(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.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 159

-Paragraph 18

-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.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)(1)

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-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 18

-Paragraph 20

-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

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.12)

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-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=16385135&loc=d3e33749-111570

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- Definition

This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.12)

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-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 9

-Article 5

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 28

-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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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

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-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 18

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- Definition

The cash outflow associated with the purchase of or advances to an equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 13

-Subparagraph (b)

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 17

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- Definition

The cash inflow associated with the sale of equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 16

-Subparagraph b

-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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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

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- Definition

Price-per-share of common or preferred stock issued or sold by the subsidiary or equity method investee.

+ References

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

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 5

-Section H

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Equity Method Investments (Narrative) (Detail) (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended				12 Months Ended							1 Months Ended	12 Months Ended					0 Months Ended	1 Months Ended			12 Months Ended			1 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2012 Janssen AI [Member]	Dec. 31, 2011 Janssen AI [Member]	Dec. 31, 2010 Janssen AI [Member]	Dec. 31, 2009 Janssen AI [Member]	Jan. 31, 2013 Janssen AI [Member] Subsequent Event [Member]	Dec. 31, 2012 Johnson & Johnson [Member]	Sep. 30, 2009 Johnson & Johnson [Member]	May 31, 2011 Proteostasis [Member]	Dec. 31, 2012 Proteostasis [Member]	Dec. 31, 2011 Proteostasis [Member]	Dec. 31, 2012 Elan Corp Plc share of losses of Jansen Ai [Member]	Dec. 31, 2011 Elan Corp Plc share of losses of Jansen Ai [Member]	Dec. 31, 2010 Elan Corp Plc share of losses of Jansen Ai [Member]	Sep. 16, 2011 Alkermes Plc [Member]	Mar. 31, 2012 Alkermes Plc [Member]	Mar. 13, 2012 Alkermes Plc [Member]	Sep. 16, 2011 Alkermes Plc [Member]	Dec. 31, 2012 Alkermes Plc [Member]	Dec. 31, 2011 Alkermes Plc [Member]	Dec. 31, 2012 Alkermes Plc [Member] Discontinued Operations [Member]	Jan. 31, 2013 Alkermes Plc [Member] Subsequent Event [Member]	Feb. 06, 2013 Alkermes Plc [Member] Subsequent Event [Member]	Sep. 16, 2011 Alkermes Inc. [Member]
Schedule of Equity Method Investments [Line Items]
Elan ownership percentage			30.00%		49.90%							24.00%						25.00%	6.00%		25.00%	25.00%
Funding commitment received with respect to collaboration	$ 400.0				$ 500.0	$ 57.6					$ 500.0
Elan and Johnson & Johnson maximum additional commitment	400.0				76.9				29.9	400.0
Unspent funding commitment						57.6
Excess of losses over investment					11.0	0
Asset impairment charge	117.3				678.9
Claim on Janssen AI book value (after adjusting for basis differences)					0	117.3
Difference between carrying amount and reported book value of net assets						185																300
Carrying value of equity method investment	14.0	675.8	209.0	235.0		130.6	209.0	235.0				20.0	14.0	17.3				528.6			528.6	528.6	527.9
Amortization expense recorded related to basis differences					13.3	50.9	26.0
Net loss in investment in associates	(221.8)	(81.1)	(26.0)		(218.5)	(78.4)	(26.0)						(3.3)	(2.7)	(87.9)							7.2	0.7
Initial funding commitment										500.0
Immaterial error from prior periods						27.5
Purchase of equity method investment		20.0										20.0
Ordinary shares																		31.90	7.75		31.90						31.90
Share price																		$ 16.57			$ 16.57						$ 16.57
Sale of ordinary shares																			76.00%
Ordinary shares																			24.15	24.15		24.15			7.75
Initial carrying value of available- for-sale investment																						126.5		126.5
Proceeds from sale of ordinary share	$ 380.9																		$ 380.9							$ 169.7