Reserves for Discounts and Allowances (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended
	Sep. 30, 2013
Analysis of the amount of, and change in, reserves
Balance, as of December 31, 2012	$ 237.1
Current provisions relating to sales in current year	768.7
Adjustments relating to prior years	(7.7)
Payments/returns relating to sales in current year	(451.4)
Payments/returns relating to sales in prior years	(155.5)
Balance, as of September 30, 2013	391.2
Discounts [Member]
Analysis of the amount of, and change in, reserves
Balance, as of December 31, 2012	15.5
Current provisions relating to sales in current year	202.9
Adjustments relating to prior years	(0.8)
Payments/returns relating to sales in current year	(145.3)
Payments/returns relating to sales in prior years	(13.8)
Balance, as of September 30, 2013	58.5
Contractual Adjustments [Member]
Analysis of the amount of, and change in, reserves
Balance, as of December 31, 2012	194.8
Current provisions relating to sales in current year	549.8
Adjustments relating to prior years	(7.8)
Payments/returns relating to sales in current year	(306.1)
Payments/returns relating to sales in prior years	(127.8)
Balance, as of September 30, 2013	302.9
Returns [Member]
Analysis of the amount of, and change in, reserves
Balance, as of December 31, 2012	26.8
Current provisions relating to sales in current year	16.0
Adjustments relating to prior years	0.9
Payments/returns relating to sales in current year	0
Payments/returns relating to sales in prior years	(13.9)
Balance, as of September 30, 2013	$ 29.8