Significant Accounting Policies - Additional Information (Detail) - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | |||
|---|---|---|---|---|---|
Sep. 30, 2017 |
Sep. 30, 2016 |
Sep. 30, 2017 |
Sep. 30, 2016 |
Jan. 01, 2017 |
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| Subsidiary or Equity Method Investee [Line Items] | |||||
| Other operating income | $ 4.6 | $ 0.2 | $ 43.5 | $ 29.1 | |
| China [Member] | |||||
| Subsidiary or Equity Method Investee [Line Items] | |||||
| Other operating income | 4.6 | $ 0.2 | 43.5 | $ 29.1 | |
| Accounting Standards Update 2016-09 [Member] | |||||
| Subsidiary or Equity Method Investee [Line Items] | |||||
| Deferred tax assets, gross | $ 29.6 | ||||
| Excess tax benefits | $ 0.6 | $ 26.4 | |||
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- Definition Excess tax benefits. No definition available.
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The total amount of other operating income, the components of which are not separately disclosed on the income statement, from items that are associated with the entity's normal revenue producing operation. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition 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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