Accumulated Other Comprehensive Loss - Schedule of Changes in AOCI (Details) $ in Millions	3 Months Ended
Mar. 31, 2020 USD ($)
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	$ 2,856.6
Other Comprehensive Income (Loss) before Reclassifications	(15.7)
Amounts Reclassified from Accumulated Other Comprehensive (Loss) Income	151.0
Net Current-period Other Comprehensive (Loss) Income	135.3
Ending balance	2,571.1
AOCI attributable to parent
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(380.2)
Ending balance	(244.9)
Derivatives Instruments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(20.8)
Ending balance	(22.5)
Pension and Postretirement Benefit Plans
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(245.5)
Currency Translation Adjustments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(113.9)
Derivatives Instruments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Other Comprehensive Income (Loss) before Reclassifications	0.9
Amounts Reclassified from Accumulated Other Comprehensive (Loss) Income	(2.6)
Net Current-period Other Comprehensive (Loss) Income	(1.7)
Pension and Postretirement Benefit Plans
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Other Comprehensive Income (Loss) before Reclassifications	40.4
Amounts Reclassified from Accumulated Other Comprehensive (Loss) Income	153.6
Net Current-period Other Comprehensive (Loss) Income	194.0
Ending balance	(51.5)
Currency Translation Adjustments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Other Comprehensive Income (Loss) before Reclassifications	(57.0)
Amounts Reclassified from Accumulated Other Comprehensive (Loss) Income	0.0
Net Current-period Other Comprehensive (Loss) Income	(57.0)
Ending balance	$ (170.9)

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

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

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- Definition

Amount of ownership interest in limited liability company (LLC), attributable to the parent entity.

+ References

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

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

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