Indebtedness - Summary of Components of Interest as Presented in Consolidated Statements of Operations (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Debt Disclosure [Abstract]
Income	$ 3.6	$ 4.1	$ 12.5	$ 10.7
Expense on borrowings	(37.4)	(46.4)	(125.7)	(147.1)
UTPs and other tax related liabilities	(7.0)	(9.6)	(20.2)	(10.6)
Net periodic pension costs - interest component	(5.6)	(4.9)	(16.8)	(14.5)
Capitalized	0.5	0.4	1.2	1.0
Total	$ (45.9)	$ (56.4)	$ (149.0)	$ (160.5)

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Amount of cost recognized for passage of time related to defined benefit plan.

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The amount of interest income and other income recognized during the period. Included in this element is interest derived from investments in debt securities, cash and cash equivalents, and other investments which reflect the time value of money or transactions in which the payments are for the use or forbearance of money and other income from ancillary business-related activities (that is, excluding major activities considered part of the normal operations of the business).

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No definition available.

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Amount of interest costs capitalized disclosed as an adjusting item to interest costs incurred.

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No definition available.

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Aggregate amount of interest expense on all borrowings.

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The net amount of nonoperating interest income (expense).

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No definition available.

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Amount of interest expense for an underpayment of income taxes.

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