Accumulated Other Comprehensive Loss - Changes in Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Increase (Decrease) in Stockholders' Equity [Roll Forward]
EQUITY, JANUARY 1			$ 1,603.2	$ 1,749.0
Amounts reclassified from accumulated other comprehensive loss	$ 2.2	$ 2.4	5.9	6.1
Current period other comprehensive income (loss)	17.4	(0.1)	39.9	(11.1)
EQUITY, SEPTEMBER 30	1,667.7	1,634.6	1,667.7	1,634.6
Accumulated net gain (loss) from cash flow hedges
Accumulated Other Comprehensive Income (Loss) [Line Items]
Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income (Loss), Effective Portion, Net			(2.3)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
EQUITY, JANUARY 1			0.0
Amounts reclassified from accumulated other comprehensive loss			0.4
Current period other comprehensive income (loss)			(1.9)
EQUITY, SEPTEMBER 30	(1.9)		(1.9)
Unrealized gain (loss) on available-for- sale securities
Increase (Decrease) in Stockholders' Equity [Roll Forward]
EQUITY, JANUARY 1			(1.2)
Other comprehensive income (loss) before reclassifications			1.0
Amounts reclassified from accumulated other comprehensive loss			0.0
Current period other comprehensive income (loss)			1.0
EQUITY, SEPTEMBER 30	(0.2)		(0.2)
Pension and post retirement benefit plan adjustment
Increase (Decrease) in Stockholders' Equity [Roll Forward]
EQUITY, JANUARY 1			(180.5)
Other comprehensive income (loss) before reclassifications			0.0
Amounts reclassified from accumulated other comprehensive loss	1.8	$ 2.1	5.5	$ 6.2
Current period other comprehensive income (loss)			5.5
EQUITY, SEPTEMBER 30	(175.0)		(175.0)
Cumulative translation adjustment
Increase (Decrease) in Stockholders' Equity [Roll Forward]
EQUITY, JANUARY 1			(120.8)
Other comprehensive income (loss) before reclassifications			35.3
Amounts reclassified from accumulated other comprehensive loss			0.0
Current period other comprehensive income (loss)			35.3
EQUITY, SEPTEMBER 30	(85.5)		(85.5)
AOCI Including Portion Attributable to Parent
Increase (Decrease) in Stockholders' Equity [Roll Forward]
EQUITY, JANUARY 1			(302.5)
Other comprehensive income (loss) before reclassifications			34.0
Amounts reclassified from accumulated other comprehensive loss			5.9
Current period other comprehensive income (loss)			39.9
EQUITY, SEPTEMBER 30	$ (262.6)		$ (262.6)