Reserves for Discounts and Allowances (Details) $ in Millions	9 Months Ended
	Sep. 30, 2017 USD ($)
Analysis of the amount of, and change in, reserves
Balance as of December 31, 2016	$ 605.5
Current provisions relating to sales in current year	2,123.2
Adjustments relating to prior years	2.4
Payments/credits relating to sales in current year	(1,547.3)
Payments/credits relating to sales in prior years	(519.2)
Balance as of September 30, 2017	664.6
Discounts
Analysis of the amount of, and change in, reserves
Balance as of December 31, 2016	71.6
Current provisions relating to sales in current year	422.0
Adjustments relating to prior years	(0.2)
Payments/credits relating to sales in current year	(320.1)
Payments/credits relating to sales in prior years	(70.4)
Balance as of September 30, 2017	102.9
Contractual Adjustments
Analysis of the amount of, and change in, reserves
Balance as of December 31, 2016	482.7
Current provisions relating to sales in current year	1,681.2
Adjustments relating to prior years	11.2
Payments/credits relating to sales in current year	(1,227.1)
Payments/credits relating to sales in prior years	(431.6)
Balance as of September 30, 2017	516.4
Returns
Analysis of the amount of, and change in, reserves
Balance as of December 31, 2016	51.2
Current provisions relating to sales in current year	20.0
Adjustments relating to prior years	(8.6)
Payments/credits relating to sales in current year	(0.1)
Payments/credits relating to sales in prior years	(17.2)
Balance as of September 30, 2017	$ 45.3