Income Taxes - Changes Occurred in Amount of Unrecognized Tax Benefits (Detail) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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| Income Tax Disclosure [Abstract] | |||
| Beginning balance of unrecognized tax benefits | $ 50.5 | $ 49.4 | $ 40.5 |
| Additions for current year tax positions | 13.0 | 9.3 | 11.3 |
| Additions for prior year tax positions | 3.6 | 2.0 | 2.5 |
| Reductions for prior year tax positions | (6.0) | (4.7) | (0.6) |
| Reductions for audit settlements | (7.1) | (0.1) | |
| Reductions for the expiration of statutes of limitation | (6.2) | (4.2) | (2.8) |
| Changes due to foreign currency translation adjustments | 2.8 | (1.3) | (1.4) |
| Ending balance of unrecognized tax benefits (excluding interest and penalties) | 50.6 | 50.5 | 49.4 |
| Interest and penalties associated with unrecognized tax benefits | 11.4 | 11.5 | 8.6 |
| Ending balance of unrecognized tax benefits (including interest and penalties) | $ 62.0 | $ 62.0 | $ 58.0 |
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- Definition Gross balance of unrecognized tax benefits including interest and penalties. No definition available.
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- Definition Unrecognized tax benefits gross interest and penalties. No definition available.
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- Definition Unrecognized tax benefits increase decrease resulting from foreign currency translation. No definition available.
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- References No definition available.
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- Definition Amount of unrecognized tax benefits. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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