Revenue Reserves (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Analysis of the amount of, and change in, reserves
Beginning balance	$ 483.8	$ 426.2	$ 237.1
Current provisions relating to sales in current year	2,229.4	1,651.8	1,120.5
Adjustments relating to prior years	(32.3)	(16.0)	(16.0)
Payments/returns relating to sales in current year	(1,666.6)	(1,237.2)	(750.1)
Payments/returns relating to sales in prior years	(351.6)	(341.0)	(165.3)
Ending balance	662.7	483.8	426.2
Discounts
Analysis of the amount of, and change in, reserves
Beginning balance	47.6	47.0	14.3
Current provisions relating to sales in current year	459.7	347.3	236.3
Adjustments relating to prior years	(1.3)	(1.0)	(0.7)
Payments/returns relating to sales in current year	(405.9)	(299.7)	(189.7)
Payments/returns relating to sales in prior years	(44.0)	(46.0)	(13.2)
Ending balance	56.1	47.6	47.0
Contractual Adjustments
Analysis of the amount of, and change in, reserves
Beginning balance	387.1	345.5	196.0
Current provisions relating to sales in current year	1,732.1	1,265.4	861.3
Adjustments relating to prior years	(16.3)	(28.5)	(16.4)
Payments/returns relating to sales in current year	(1,258.1)	(933.4)	(560.4)
Payments/returns relating to sales in prior years	(296.1)	(261.9)	(135.0)
Ending balance	548.7	387.1	345.5
Returns
Analysis of the amount of, and change in, reserves
Beginning balance	49.1	33.7	26.8
Current provisions relating to sales in current year	37.6	39.1	22.9
Adjustments relating to prior years	(14.7)	13.5	1.1
Payments/returns relating to sales in current year	(2.6)	(4.1)	0.0
Payments/returns relating to sales in prior years	(11.5)	(33.1)	(17.1)
Ending balance	$ 57.9	$ 49.1	$ 33.7