Income Taxes - Deferred Taxes (Detail) - USD ($) $ in Millions	Dec. 31, 2018	Jan. 01, 2018	Dec. 31, 2017
Income Taxes [Line Items]
Other non-current assets	$ 26.2		$ 29.0
Deferred tax liabilities	105.9	$ 105.0	108.6
Total deferred tax liabilities	$ 79.7		$ 79.6

Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards classified as noncurrent.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant