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

No definition available.

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- Definition

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

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- Definition

Amount after tax of other comprehensive income (loss) attributable to parent entity.

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

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- Definition

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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Accumulated Other Comprehensive Income (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance			$ (1,326.5)
Other comprehensive income before reclassifications			(26.7)
Amounts reclassified from accumulated other comprehensive income	$ 38.6	$ 38.0	77.3	$ 72.9
Current period other comprehensive income			50.6
Ending balance	(1,244.1)		(1,244.1)
Total
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance			(3,815.8)
Ending balance	(3,765.2)		(3,765.2)
Translation Adjustments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance			(817.0)
Other comprehensive income before reclassifications			(27.5)
Amounts reclassified from accumulated other comprehensive income			0.0
Current period other comprehensive income			(27.5)
Ending balance	(844.5)		(844.5)
Postretirement Plans
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance			(2,998.8)
Other comprehensive income before reclassifications			0.8
Amounts reclassified from accumulated other comprehensive income			77.3
Current period other comprehensive income			78.1
Ending balance	$ (2,920.7)		$ (2,920.7)