Borrowings - Reclassifications and Revisions (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Debt Instrument [Line Items]
Net income	$ (24.3)	$ 55.8	$ 22.4	$ 52.1
Provision (benefit) for income taxes	$ 29.5	(1.3)	$ 30.7	10.7
Restatement Adjustment [Member] | Determination of Effective Interest Rate Amortization [Member]
Debt Instrument [Line Items]
Net income		2.5		5.3
Interest expense, debt		2.9		6.0
Provision (benefit) for income taxes		$ 0.4		$ 0.7