Accounts Receivable, Net (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Provision for discounts and doubtful accounts
As at January 1,	$ 48.5	$ 47.9
Provision charged to operations	186.6	163.1
Provision utilization	(181.6)	(165.7)
As at June 30,	53.5	$ 45.3
Accounts receivable, net	1,099.2		$ 1,035.1
Accounts receivable related to royalty income	$ 69.8		$ 59.0