Accumulated Other Comprehensive Loss - Schedule of Income Tax (Provision) Benefit Allocated to Components of OCI (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Equity [Abstract]
Foreign currency translation adjustments	$ (0.1)	$ 1.9	$ (0.6)	$ 0.8
Unrecognized pension and postretirement costs	3.9	1.5	11.9	4.2
Derivative financial instruments	$ (3.8)	(1.1)	(13.8)	(7.7)
Income tax (provision) benefit related to OCI		$ 2.3	$ (2.5)	$ (2.7)

No definition available.

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Amount of tax expense (benefit), after reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

+ References

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-Name Accounting Standards Codification
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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss).

+ References

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Amount of tax (expense) benefit for reclassification adjustment from accumulated other comprehensive (income) loss of defined benefit plan.

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Amount of tax expense (benefit) allocated to other comprehensive income (loss).

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