Accumulated Other Comprehensive (Loss) - Schedule of Changes in AOCI (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	$ 2,058.0	$ 2,018.5
Other Comprehensive Income (Loss) before Reclassifications	(24.1)
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)	120.9
Net Current-period Other Comprehensive (Loss) Income	96.8
Net Current-period Other Comprehensive Loss (Income) Attributable to Noncontrolling Interest	96.8	6.0
Ending balance	2,010.3	2,005.3
AOCI Attributable to Parent
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(365.8)	(377.9)
Ending balance	(299.5)	$ (373.2)
Derivatives Instruments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(16.6)
Ending balance	(17.6)
Pension and Postretirement Benefit Plans
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(238.5)
Ending balance	(125.2)
Currency Translation Adjustments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(110.7)
Ending balance	(156.7)
Derivatives Instruments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Other Comprehensive Income (Loss) before Reclassifications	0.7
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)	(2.1)
Net Current-period Other Comprehensive (Loss) Income	(1.4)
Pension and Postretirement Benefit Plans
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Other Comprehensive Income (Loss) before Reclassifications	32.1
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)	123.0
Net Current-period Other Comprehensive (Loss) Income	155.1
Currency Translation Adjustments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Other Comprehensive Income (Loss) before Reclassifications	(56.9)
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)	0.0
Net Current-period Other Comprehensive (Loss) Income	(56.9)
Derivatives Instruments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Net Current-period Other Comprehensive Loss (Income) Attributable to Noncontrolling Interest	0.4
Pension and Postretirement Benefit Plans
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Net Current-period Other Comprehensive Loss (Income) Attributable to Noncontrolling Interest	(41.8)
Currency Translation Adjustments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Net Current-period Other Comprehensive Loss (Income) Attributable to Noncontrolling Interest	10.9
Total
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Net Current-period Other Comprehensive Loss (Income) Attributable to Noncontrolling Interest	$ (30.5)

Other Comprehensive Income (Loss), Net of Tax, Including Redeemable Noncontrolling Interest

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Amount after tax, before reclassification adjustments of other comprehensive income (loss).

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity.

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