| Segment Information - Reconciliation of Operating Profit (Loss) from Segments to Consolidated (Parenthetical) (Detail) - USD ($) $ in Millions | 3 Months Ended | |
|---|---|---|
| Mar. 31, 2021 | Mar. 31, 2020 | |
| Selling, General and Administrative Expenses [Member] | China [Member] | ||
| Segment Reporting Reconciling Item For Operating Profit Loss From Segment To Consolidated [Line Items] | ||
| Independent service providers service fees costs | $ 95.0 | $ 105.7 | 
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- Definition Independent service providers service fee costs. No definition available. 
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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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| X | ||||||||||
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- Details 
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- Details 
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