Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	3 Months Ended				6 Months Ended
	Jun. 30, 2018		Jun. 30, 2017		Jun. 30, 2018		Jun. 30, 2017
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	$ (992.2)		$ (1,071.4)		$ (1,027.8)		$ (1,093.7)
OCI before reclassifications	(15.6)		0.1		3.6		5.9
Amounts reclassified from AOCI	16.2		4.1		32.6		20.6
Net current-period OCI	0.6		4.2		36.2		26.5
Ending balance	(991.6)		(1,067.2)		(991.6)		(1,067.2)
Increase (Decrease) in Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Beginning balance	24.2		11.7		17.3		9.7
OCI before reclassifications	(3.1)		0.2		3.8		2.2
Amounts reclassified from AOCI	0.0		0.0		0.0		0.0
Net current-period OCI	(3.1)		0.2		3.8		2.2
Ending balance	21.1		11.9		21.1		11.9
Post- retirement benefit plans [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	(940.2)		(954.7)		(954.5)		(965.5)
OCI before reclassifications	0.0		0.0		0.0		0.0
Amounts reclassified from AOCI	14.0	[1]	11.2	[2]	28.3	[1]	22.0	[2]
Net current-period OCI	14.0		11.2		28.3		22.0
Ending balance	(926.2)		(943.5)		(926.2)		(943.5)
Increase (Decrease) in Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Beginning balance	0.0		0.0		0.0		0.0
OCI before reclassifications	0.0		0.0		0.0		0.0
Amounts reclassified from AOCI	0.0		0.0		0.0		0.0
Net current-period OCI	0.0		0.0		0.0		0.0
Ending balance	0.0		0.0		0.0		0.0
Currency translation adjustment [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	(36.8)		(76.6)		(53.5)		(85.0)
OCI before reclassifications	(23.1)		4.2		(6.4)		12.6
Amounts reclassified from AOCI	0.0	[3]	0.0	[4]	0.0	[3]	0.0	[4]
Net current-period OCI	(23.1)		4.2		(6.4)		12.6
Ending balance	(59.9)		(72.4)		(59.9)		(72.4)
Increase (Decrease) in Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Beginning balance	24.2		11.7		17.3		9.7
OCI before reclassifications	(3.1)		0.2		3.8		2.2
Amounts reclassified from AOCI	0.0	[3]	0.0	[4]	0.0	[3]	0.0	[4]
Net current-period OCI	(3.1)		0.2		3.8		2.2
Ending balance	21.1		11.9		21.1		11.9
Unrealized holding gains on securities [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	0.0		0.0		0.0		0.0
OCI before reclassifications	0.0		0.0		0.0		0.0
Amounts reclassified from AOCI	0.0	[3]	0.0	[4]	0.0	[3]	0.0	[4]
Net current-period OCI	0.0		0.0		0.0		0.0
Ending balance	0.0		0.0		0.0		0.0
Increase (Decrease) in Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Beginning balance	0.0		0.0		0.0		0.0
OCI before reclassifications	0.0		0.0		0.0		0.0
Amounts reclassified from AOCI	0.0		0.0		0.0		0.0
Net current-period OCI	0.0		0.0		0.0		0.0
Ending balance	0.0		0.0		0.0		0.0
Derivatives [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	9.2		0.3		9.0		2.4
OCI before reclassifications	7.5		(5.2)		10.0		(6.7)
Amounts reclassified from AOCI	(3.5)	[5]	(0.8)	[6]	(5.8)	[5]	(1.4)	[6]
Net current-period OCI	4.0		(6.0)		4.2		(8.1)
Ending balance	13.2		(5.7)		13.2		(5.7)
Increase (Decrease) in Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Beginning balance	0.0		0.0		0.0		0.0
OCI before reclassifications	0.0		0.0		0.0		0.0
Amounts reclassified from AOCI	0.0		0.0		0.0		0.0
Net current-period OCI	0.0		0.0		0.0		0.0
Ending balance	0.0		0.0		0.0		0.0
Accumulated Deferred Tax Asset Valuation Allowance [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	(24.4)		(40.4)		(28.8)		(45.6)
OCI before reclassifications	0.0		1.1		0.0		0.0
Amounts reclassified from AOCI	5.7	[7]	(6.3)		10.1	[7]	0.0
Net current-period OCI	5.7		(5.2)		10.1		0.0
Ending balance	(18.7)		(45.6)		(18.7)		(45.6)
Increase (Decrease) in Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Beginning balance	0.0		0.0		0.0		0.0
OCI before reclassifications	0.0		0.0		0.0		0.0
Amounts reclassified from AOCI	0.0		0.0		0.0		0.0
Net current-period OCI	0.0		0.0		0.0		0.0
Ending balance	$ 0.0		$ 0.0		$ 0.0		$ 0.0

[1] Amounts were included in net periodic benefit cost for pension and other postretirement benefit plans (see Note 9).

[2] Amounts were included in net periodic benefit cost for pension and other postretirement benefit plans (see Note 9).

[3] No amounts were reclassified to earnings.

[4] No amounts were reclassified to earnings.

[5] Amounts related to derivatives are included in cost of goods sold in the period or periods the hedged item affects earnings (see Note 7).

[6] Amounts related to the effective portion of the derivatives are included in cost of goods sold in the period or periods the hedged item affects earnings (see Note 7).

[7] Represents the net change in deferred tax asset valuation allowances on changes in AOCI balances between the balance sheet dates.