Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Changes in accumulated other comprehensive income (loss), net of tax
Balance			$ 1,588.6
Other comprehensive (loss) income, net of tax	$ (2.1)	$ (2.0)	3.6	$ (5.2)
Balance	1,838.7		1,838.7
Accumulated Other Comprehensive Income/(Loss)
Changes in accumulated other comprehensive income (loss), net of tax
Balance			(20.4)
Other comprehensive income (loss)			3.6
Other comprehensive (loss) income, net of tax			3.6
Balance	(16.8)		(16.8)
Defined Benefit Pension Plan
Changes in accumulated other comprehensive income (loss), net of tax
Balance			(5.3)
Other comprehensive income (loss)			6.4
Other comprehensive (loss) income, net of tax			6.4
Balance	1.1		1.1
Foreign Currency Translation Losses
Changes in accumulated other comprehensive income (loss), net of tax
Balance			(15.1)
Other comprehensive income (loss)			(2.8)
Other comprehensive (loss) income, net of tax			(2.8)
Balance	$ (17.9)		$ (17.9)