Schedule of Accumulated Other Comprehensive Loss (Parenthetical) (Detail) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Accumulated Other Comprehensive Income (Loss) [Line Items]
Unrealized net (loss) gain on cash flow derivative instruments, related income tax benefit (provision)	$ 0.6	$ (0.1)
Pension liability, related income tax benefit	$ 175.9	$ 183.4

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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