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Definition: Income statement classification and amounts attributable to transactions arising from the collaborative arrangement between participants for each period an income statement is presented.

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Description of rights and obligations under the collaborative arrangements - percent share in various revenues and costs.

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Revenues from the sale of other goods or rendering of other services, not elsewhere specified in the taxonomy; net of (reduced by) sales adjustments, returns, allowances, and discounts.

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

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-Name Regulation S-X (SX)

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-Section 03

-Paragraph 1

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

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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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-SubTopic 20

-Section 50

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Aggregate revenue recognized during the period (derived from goods sold, services rendered, insurance premiums, or other activities that constitute an entity's earning process). For financial services companies, also includes investment and interest income, and sales and trading gains.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

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Aggregate revenue during the period from the sale of goods in the normal course of business, after deducting returns, allowances and discounts.

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

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Collaborations (Details) In Millions, unless otherwise specified	1 Months Ended	3 Months Ended			9 Months Ended		3 Months Ended			12 Months Ended	3 Months Ended						12 Months Ended	3 Months Ended	12 Months Ended	3 Months Ended			9 Months Ended	3 Months Ended					9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended
	Mar. 31, 2010 USD ($)	Sep. 30, 2011 USD ($)	Mar. 31, 2011 USD ($)	Sep. 30, 2010 USD ($)	Sep. 30, 2011 USD ($)	Sep. 30, 2010 USD ($)	Mar. 31, 2010 United States [Member] Research and Development Exp [Member] Necitumumab [Member]	Mar. 31, 2010 Outside the United States [Member] Research and Development Exp [Member] Necitumumab [Member]	Sep. 30, 2011 Exenatide [Member] Sales NEW [Member]	Dec. 31, 2008 Prepaid Supply or COGS [Member] Exenatide Once Weekly [Member] USD ($)	Sep. 30, 2011 Exenatide [Member] Gross Margin Share [Member]	Sep. 30, 2010 Profit and Development and Marketing Share [Member] Effient [Member]	Mar. 31, 2010 Selling and Marketing Expense [Member] Necitumumab [Member]	Mar. 31, 2010 Prepaid Selling and Marketing Expense [Member] Duloxetine BI [Member] USD ($)	Mar. 31, 2010 Research and Development Exp [Member] Necitumumab [Member]	Sep. 30, 2011 Exenatide [Member] Research and Development and Marketing and Selling Expense [Member]	Dec. 31, 2008 Capital Expense [Member] Exenatide Once Weekly [Member] USD ($)	Sep. 30, 2011 Capital Expense [Member] Exenatide Once Weekly Pen [Member] USD ($)	Dec. 31, 2008 Capital Expense [Member] Exenatide Once Weekly Pen [Member] USD ($)	Mar. 31, 2010 Milestone Payments [Member] Necitumumab [Member] USD ($)	Sep. 30, 2011 Milestone Payments [Member] TPG-Axon [Member] USD ($)	Mar. 31, 2011 Milestone Payments [Member] BI compounds [Member] EUR (€)	Sep. 30, 2011 Milestone Payments [Member] BI compounds [Member] USD ($)	Mar. 31, 2011 Milestone Payments [Member] LLY compounds [Member] USD ($)	Mar. 31, 2011 Milestone Payments [Member] LLY optional compound [Member] USD ($)	Jun. 30, 2011 Loan Commitment [Member] Exenatide Once Weekly [Member] USD ($)	Sep. 30, 2011 Erbitux [Member] USD ($)	Sep. 30, 2010 Erbitux [Member] USD ($)	Sep. 30, 2011 Erbitux [Member] USD ($)	Sep. 30, 2010 Erbitux [Member] USD ($)	Sep. 30, 2011 Exenatide [Member] USD ($)	Sep. 30, 2010 Exenatide [Member] USD ($)	Sep. 30, 2011 Exenatide [Member] USD ($)	Sep. 30, 2010 Exenatide [Member] USD ($)	Sep. 30, 2011 Effient [Member] USD ($)	Sep. 30, 2010 Effient [Member] USD ($)	Sep. 30, 2011 Effient [Member] USD ($)	Sep. 30, 2010 Effient [Member] USD ($)
Net product sales		$ 5,971.7		$ 5,486.8	$ 17,748.1	$ 16,408.6																					$ 16.2	$ 18.5	$ 61.2	$ 56.9	$ 46.4	$ 39.1	$ 131.9	$ 126.0	$ 83.5	$ 36.3	$ 211.5	$ 67.9
Collaboration and other revenue		176.2		168.0	491.8	480.4																					81.1	76.9	240.1	234.7	60.3	63.6	180.5	199.3
Revenue		6,147.9		5,654.8	18,239.9	16,889.0																					97.3	95.4	301.3	291.6	106.7	102.7	312.4	325.3
Research and development		1,280.9		1,219.8	3,665.5	3,446.1
Collaborative Arrangement, Income Statement Classification and Amounts		58.6		35.6	155.5	132.2
Collaborative Arrangement, Nature and Purpose New																	550
Collaborative Arrangement, Rights and Obligations										125.0				400.0				105.0	130.0	250.0	70.0	300.0	478.7	650.0	525.0	165.0
Collaborative Arrangement, Rights and Obligations Percent							45.00%	72.50%	100.00%		50.00%	50.00%	50.00%		45.00%	50.00%			60.00%
Acquired in-process research and development	$ 50.0	$ 0	$ 388.0	$ 0	$ 388.0	$ 50.0