Segmental Reporting (by Segment) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended				9 Months Ended
	Sep. 30, 2012		Sep. 30, 2011		Sep. 30, 2012		Sep. 30, 2011		Dec. 31, 2011
Segment reporting, operating income/(loss)
Product sales	$ 1,054.5		$ 1,018.4		$ 3,309.1		$ 2,901.0
Royalties	41.8		62.8		154.4		199.8
Other revenues	4.1		4.9		16.5		20.4
Total revenues	1,100.4		1,086.1		3,480.0		3,121.2
Cost of product sales	167.9	[1]	166.5	[1]	478.8	[1]	434.7	[1]
Research and development	224.7	[1]	201.5	[1]	683.6	[1]	556.3	[1]
Selling, general and administrative ("SG&A")	437.4	[1]	452.1	[1]	1,448.4	[1]	1,295.3	[1]
(Gain)/loss on sale of product rights	(5.7)		0.3		(16.5)		3.8
Reorganization costs	0		5.0		0		18.0
Integration and acquisition costs	2.7		5.3		15.1		7.9
Total operating expenses	827.0		830.7		2,609.4		2,316.0
Operating income/(loss)	273.4		255.4		870.6		805.2
Assets	7,316.5		6,065.6		7,316.5		6,065.6		6,380.2
Long-lived assets	933.5		921.2		933.5		921.2
Capital expenditure on long-lived assets	35.3		47.1		89.1		141.9
Segment reporting, additional information
Impairment of intangible assets	0		16.0		27.0		16.0
Cost of Product Sales
Segment reporting, additional information
Depreciation from manufacturing plants	9.4		10.8		23.6		29.0
Amortization of favorable manufacturing contracts	0		0.5		0.7		1.4
Research and Development
Segment reporting, additional information
Depreciation of research and development assets	5.5		5.6		18.3		16.4
Impairment of intangible assets	0		16.0		27.0		16.0
Selling, General and Administrative
Segment reporting, additional information
Other depreciation and amortization	64.2		63.1		188.9		165.5
Specialty Pharmaceuticals
Segment reporting, operating income/(loss)
Product sales	683.4		658.0		2,125.6		1,948.8
Royalties	31.0		45.2		118.8		134.6
Other revenues	3.7		3.6		15.6		15.9
Total revenues	718.1		706.8		2,260.0		2,099.3
Cost of product sales	85.7	[2]	88.4	[3]	257.6	[4]	264.0	[5]
Research and development	137.8	[2]	121.6	[3]	427.1	[4]	329.3	[5]
Selling, general and administrative ("SG&A")	256.6	[2]	273.8	[3]	868.3	[4]	833.8	[5]
(Gain)/loss on sale of product rights	(5.7)		0.3		(16.5)		3.8
Reorganization costs			3.2		0		8.2
Integration and acquisition costs	1.4		1.7		5.5		(2.6)
Total operating expenses	475.8		489.0		1,542.0		1,436.5
Operating income/(loss)	242.3		217.8		718.0		662.8
Assets	2,565.0		2,527.9		2,565.0		2,527.9
Long-lived assets	136.0	[6]	136.2	[6]	136.0	[6]	136.2	[6]
Capital expenditure on long-lived assets	16.1	[6]	12.8	[6]	37.7	[6]	35.9	[6]
Human Genetic Therapies
Segment reporting, operating income/(loss)
Product sales	337.4		310.4		1,048.6		900.2
Royalties	0		0		0		0
Other revenues	0.4		0.3		0.9		0.9
Total revenues	337.8		310.7		1,049.5		901.1
Cost of product sales	66.2	[2]	59.9	[3]	178.2	[4]	152.2	[5]
Research and development	80.8	[2]	76.5	[3]	243.1	[4]	223.5	[5]
Selling, general and administrative ("SG&A")	87.4	[2]	85.3	[3]	296.7	[4]	257.3	[5]
(Gain)/loss on sale of product rights	0		0		0		0
Reorganization costs			0		0		0
Integration and acquisition costs	0		0		0		0
Total operating expenses	234.4		221.7		718.0		633.0
Operating income/(loss)	103.4		89.0		331.5		268.1
Assets	1,938.5		1,835.2		1,938.5		1,835.2
Long-lived assets	697.8	[6]	703.7	[6]	697.8	[6]	703.7	[6]
Capital expenditure on long-lived assets	5.8	[6]	30.1	[6]	25.2	[6]	93.9	[6]
Regenerative Medicine
Segment reporting, operating income/(loss)
Product sales	33.7		50.0		134.9		52.0
Royalties	0		0		0		0
Other revenues	0		0		0		0
Total revenues	33.7		50.0		134.9		52.0
Cost of product sales	16.0	[2]	18.2	[3]	43.0	[4]	18.5	[5]
Research and development	6.1	[2]	3.4	[3]	13.4	[4]	3.5	[5]
Selling, general and administrative ("SG&A")	37.9	[2]	30.2	[3]	122.1	[4]	31.5	[5]
(Gain)/loss on sale of product rights	0		0		0		0
Reorganization costs			0		0		0
Integration and acquisition costs	1.3		3.6		9.6		10.5
Total operating expenses	61.3		55.4		188.1		64.0
Operating income/(loss)	(27.6)		(5.4)		(53.2)		(12.0)
Assets	963.0		972.7		963.0		972.7
Long-lived assets	28.7	[6]	20.2	[6]	28.7	[6]	20.2	[6]
Capital expenditure on long-lived assets	5.0	[6]	0.5	[6]	9.7	[6]	0.7	[6]
All Other Segment
Segment reporting, operating income/(loss)
Product sales	0		0		0		0
Royalties	10.8		17.6		35.6		65.2
Other revenues	0		1.0		0		3.6
Total revenues	10.8		18.6		35.6		68.8
Cost of product sales	0	[2]	0	[3]	0	[4]	0	[5]
Research and development	0	[2]	0	[3]	0	[4]	0	[5]
Selling, general and administrative ("SG&A")	55.5	[2]	62.8	[3]	161.3	[4]	172.7	[5]
(Gain)/loss on sale of product rights	0		0		0		0
Reorganization costs			1.8		0		9.8
Integration and acquisition costs	0		0		0		0
Total operating expenses	55.5		64.6		161.3		182.5
Operating income/(loss)	(44.7)		(46.0)		(125.7)		(113.7)
Assets	1,850.0		729.8		1,850.0		729.8
Long-lived assets	71.0	[6]	61.1	[6]	71.0	[6]	61.1	[6]
Capital expenditure on long-lived assets	$ 8.4	[6]	$ 3.7	[6]	$ 16.5	[6]	$ 11.4	[6]

[1] Cost of product sales includes amortization of intangible assets relating to favorable manufacturing contracts of $nil for the three months to September 30, 2012 (2011: $0.5 million) and $0.7 million for the nine months to September 30, 2012 (2011: $1.4 million). Research and development costs include intangible asset impairment charges of $nil (2011: $16.0 million) for the three months to September 30, 2012 and $27.0 million for the nine months to September 30, 2012 (2011: $16.0 million). SG&A costs includes amortization of intangible assets relating to intellectual property rights acquired of $50.0 million for the three months to September 30, 2012 (2011: $46.4 million) and $146.6 million for the nine months to September 30, 2012 (2011: $119.1 million.)

[2] (1) Depreciation from manufacturing plants ($9.4 million) is included in Cost of product sales; depreciation of research and development assets ($5.5 million) is included in Research and development; and all other depreciation and amortization ($64.2 million) is included in Selling, general and administrative.

[3] (1) Depreciation from manufacturing plants ($10.8 million) and amortization of favorable manufacturing contracts ($0.5 million) is included in Cost of product sales; depreciation of research and development assets ($5.6 million) and impairment of certain 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 charges ($63.1 million) is included in Selling, general and administrative.

[4] (1) Depreciation from manufacturing plants ($23.6 million) and amortization of favorable manufacturing contracts ($0.7 million) is included in Cost of product sales; depreciation of research and development assets ($18.3 million) and impairment of IPR&D intangible assets in the SP reporting segment ($27.0 million) is included in Research and development; and all other depreciation and amortization ($188.9 million) is included in Selling, general and administrative.

[5] (1) Depreciation from manufacturing plants ($29.0 million) and amortization of favorable manufacturing contracts ($1.4 million) is included in Cost of product sales; depreciation of research and development assets ($16.4 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 ($165.5 million) is included in Selling, general and administrative.

[6] (2) 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).