Revenue Reserves (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Analysis of the amount of, and change in, reserves
Beginning balance	$ 416.3	$ 237.1	$ 155.6
Current provisions relating to sales in current year	1,645.2	1,110.6	652.7
Adjustments relating to prior years	(14.7)	(16.0)	(5.1)
Payments/returns relating to sales in current year	(1,237.2)	(750.1)	(451.1)
Payments/returns relating to sales in prior years	(341.0)	(165.3)	(115.0)
Ending balance	468.6	416.3	237.1
Discounts
Analysis of the amount of, and change in, reserves
Beginning balance	47.0	14.3	11.9
Current provisions relating to sales in current year	347.3	236.3	96.5
Adjustments relating to prior years	(1.0)	(0.7)	(0.3)
Payments/returns relating to sales in current year	(299.7)	(189.7)	(83.6)
Payments/returns relating to sales in prior years	(46.0)	(13.2)	(10.2)
Ending balance	47.6	47.0	14.3
Contractual Adjustments
Analysis of the amount of, and change in, reserves
Beginning balance	335.6	196.0	120.0
Current provisions relating to sales in current year	1,258.8	851.4	534.2
Adjustments relating to prior years	(27.2)	(16.4)	(4.7)
Payments/returns relating to sales in current year	(933.4)	(560.4)	(363.2)
Payments/returns relating to sales in prior years	(261.9)	(135.0)	(90.3)
Ending balance	371.9	335.6	196.0
Returns
Analysis of the amount of, and change in, reserves
Beginning balance	33.7	26.8	23.7
Current provisions relating to sales in current year	39.1	22.9	22.0
Adjustments relating to prior years	13.5	1.1	(0.1)
Payments/returns relating to sales in current year	(4.1)	0	(4.3)
Payments/returns relating to sales in prior years	(33.1)	(17.1)	(14.5)
Ending balance	$ 49.1	$ 33.7	$ 26.8

Adjustments to product revenue reserves relating to sales in prior years.

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- Definition

Current provisions to product revenue reserves relating to sales in current year.

+ References

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- Definition

Payments/ returns applied against product revenue reserves relating to current year.

+ References

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Payments/ returns applied against product revenue reserves relating to prior year.

+ References

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- Definition

Total of allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 09

-Article 12

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