Segmental Reporting (by Segment) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended										12 Months Ended
	Dec. 31, 2012		Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011		Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012		Dec. 31, 2011		Dec. 31, 2010
Segment reporting, operating income/(loss)
Product sales											$ 4,406.7		$ 3,950.2		$ 3,128.2
Royalties											241.6		283.5		328.1
Other revenues											32.9		29.7		14.8
Total revenues	1,201.2		1,100.4	1,207.8	1,171.8	1,142.2		1,086.1	1,062.9	972.7	4,681.2		4,263.4		3,471.1
Cost of product sales											645.4	[1],[2]	588.1	[1],[3]	463.4	[1],[4]
Research and development											965.5	[1],[2]	770.7	[1],[3]	661.5	[1],[4]
Selling, general and administrative											2,114.0	[1],[2]	1,751.4	[1],[3]	1,526.3	[1],[4]
(Gain)/loss on sale of product rights											(18.1)		6.0		(16.5)
Reorganization costs											0		24.3		34.3
Integration and acquisition costs											25.2		13.7		8.0
Total operating expenses											3,732.0		3,154.2		2,677.0
Operating income/(loss)	78.6		273.4	302.2	295.0	304.0		255.4	283.3	266.5	949.2		1,109.2		794.1
Assets	7,317.2					6,380.2					7,317.2		6,380.2		5,387.6
Long-lived assets	957.2	[5]				933.7	[5]				957.2	[5]	933.7	[5]	857.4	[6]
Capital expenditure on long-lived assets											146.2	[5]	204.2	[5]	315.8	[6]
Segment reporting, additional information
Amortization of intangible assets											194.8		166.7
Impairment of unamortized intangible assets											71.2		16.0		0
Cost of Product Sales
Segment reporting, additional information
Depreciation from manufacturing plants											31.5		39.8		38.1
Selling, General and Administrative
Segment reporting, additional information
Other depreciation and amortization											380.6		228.1		238.3
Favorable Manufacturing Contract | Cost of Product Sales
Segment reporting, additional information
Amortization of intangible assets											0.7		1.7		1.7
Research and Development Assets | Research and Development
Segment reporting, additional information
Amortization of intangible assets											22.5		25.2		19.0
Specialty Pharmaceuticals
Segment reporting, operating income/(loss)
Product sales											2,834.9		2,615.6		2,219.2
Royalties											148.8		199.6		173.3
Other revenues											31.7		24.5		7.1
Total revenues											3,015.4		2,839.7		2,399.6
Cost of product sales											345.4	[2]	351.7	[3]	332.1	[4]
Research and development											617.4	[2]	449.1	[3]	348.9	[4]
Selling, general and administrative											1,354.1	[2]	1,131.3	[3]	1,035.8	[4]
(Gain)/loss on sale of product rights											(18.1)		6.0		(16.5)
Reorganization costs													11.8		13.0
Integration and acquisition costs											12.1		0.1		8.0
Total operating expenses											2,310.9		1,950.0		1,721.3
Operating income/(loss)											704.5		889.7		678.3
Assets	2,370.8					2,421.7					2,370.8		2,421.7		2,483.5
Long-lived assets	138.8	[5]				126.8	[5]				138.8	[5]	126.8	[5]	154.7	[6]
Capital expenditure on long-lived assets											64.5	[5]	54.4	[5]	21.8	[6]
Specialty Pharmaceuticals | IPR&D | Research and Development
Segment reporting, additional information
Impairment of unamortized intangible assets											71.2		16.0
Human Genetic Therapies
Segment reporting, operating income/(loss)
Product sales											1,418.0		1,229.3		909.0
Royalties											0		0		0
Other revenues											1.2		1.2		2.6
Total revenues											1,419.2		1,230.5		911.6
Cost of product sales											240.4	[2]	200.0	[3]	129.3	[4]
Research and development											329.1	[2]	315.4	[3]	312.2	[4]
Selling, general and administrative											384.4	[2]	340.6	[3]	297.7	[4]
(Gain)/loss on sale of product rights											0		0		0
Reorganization costs													0		0
Integration and acquisition costs											0.5		0		0
Total operating expenses											954.4		856.0		739.2
Operating income/(loss)											464.8		374.5		172.4
Assets	1,941.6					1,849.4					1,941.6		1,849.4		1,786.9
Long-lived assets	698.2	[5]				720.8	[5]				698.2	[5]	720.8	[5]	655.4	[6]
Capital expenditure on long-lived assets											42.1	[5]	129.4	[5]	281.1	[6]
Regenerative Medicine
Segment reporting, operating income/(loss)
Product sales											153.8		105.3		0
Royalties											0		0		0
Other revenues											0		0		0
Total revenues											153.8		105.3		0
Cost of product sales											59.6	[2]	36.4	[3]	0	[4]
Research and development											19.0	[2]	6.2	[3]	0	[4]
Selling, general and administrative											161.8	[2]	64.4	[3]	0	[4]
(Gain)/loss on sale of product rights											0		0		0
Reorganization costs													0		0
Integration and acquisition costs											12.6		13.6		0
Total operating expenses											253.0		120.6		0
Operating income/(loss)											(99.2)		(15.3)		0
Assets	945.8					967.7					945.8		967.7		0
Long-lived assets	36.2	[5]				22.9	[5]				36.2	[5]	22.9	[5]	0	[6]
Capital expenditure on long-lived assets											9.7	[5]	1.5	[5]	0	[6]
All Other Segment
Segment reporting, operating income/(loss)
Product sales											0		0		0
Royalties											92.8		83.9		154.8
Other revenues											0		4.0		5.1
Total revenues											92.8		87.9		159.9
Cost of product sales											0	[2]	0	[3]	2.0	[4]
Research and development											0	[2]	0	[3]	0.4	[4]
Selling, general and administrative											213.7	[2]	215.1	[3]	192.8	[4]
(Gain)/loss on sale of product rights											0		0		0
Reorganization costs													12.5		21.3
Integration and acquisition costs											0		0		0
Total operating expenses											213.7		227.6		216.5
Operating income/(loss)											(120.9)		(139.7)		(56.6)
Assets	2,059.0					1,141.4					2,059.0		1,141.4		1,117.2
Long-lived assets	83.9	[5]				63.2	[5]				83.9	[5]	63.2	[5]	47.3	[6]
Capital expenditure on long-lived assets											$ 29.5	[5]	$ 18.9	[5]	$ 12.9	[6]

[1] Cost of product sales includes amortization of intangible assets relating to favorable manufacturing contracts of $0.7 million for the year to December 31, 2012 (2011: $1.7 million, 2010: $1.7 million). Research and development costs include intangible asset impairment charges of $71.2 million for the year to December 31, 2012 (2011: $16.0 million, 2010: $nil). SG&A costs includes amortization and impairment charges of intangible assets relating to intellectual property rights acquired of $320.8 million including impairment losses of $126.7 million for the year to December 31, 2012 (2011: $165.0 million including impairment losses of $nil, 2010: $176.2 million including impairment losses of $42.7 million).

[2] Depreciation from manufacturing plants ($31.5 million) and amortization of favorable manufacturing contracts ($0.7 million) is included in Cost of product sales; depreciation of research and development assets ($22.5 million) and impairment of IPR&D intangible assets in the SP reporting segment ($71.2 million) is included in Research and development; and all other depreciation, amortization and impairment of ($380.6 million) is included in Selling, general and administrative.

[3] Depreciation from manufacturing plants ($39.8 million) and amortization of favorable manufacturing contracts ($1.7 million) is included in Cost of product sales; depreciation of research and development assets ($25.2 million) and impairment of IPR&D intangible assets in the SP reporting segment ($16.0 million) is included in Research and development; and all other depreciation, amortization and impairment ($228.1 million) is included in Selling, general and administrative.

[4] Depreciation from manufacturing plants ($38.1 million) and amortization of favorable manufacturing contracts ($1.7 million) is included in Cost of product sales; depreciation of research and development assets ($19.0 million) is included in Research and development; and all other depreciation and amortization ($238.3 million) is included in Selling, general and administrative.

[5] Long-lived assets comprise all non-current assets (excluding goodwill and other intangible assets, deferred contingent consideration assets, deferred tax assets, investments, income tax receivable and financial instruments).

[6] Long-lived assets comprise all non-current assets, (excluding goodwill and other intangible assets, deferred contingent consideration assets, deferred tax assets, investments, income tax receivable and financial instruments).