Income Taxes - Additional Information (Detail) - USD ($) $ in Millions  | 
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2021  | 
Jun. 30, 2020  | 
Jun. 30, 2021  | 
Jun. 30, 2020  | 
|
| Income Tax Disclosure [Abstract] | ||||
| Income taxes | $ 32.3 | $ 45.8 | $ 69.9 | $ 70.8 | 
| Effective income tax rate | 18.30% | 28.50% | 19.40% | 30.60% | 
| Total amount of unrecognized tax benefits, including related interest and penalties | $ 69.0 | $ 69.0 | ||
| Unrecognized tax benefits excluding interest and penalties that if recognized would affect the effective tax rate | 45.3 | 45.3 | ||
| Total accrued interest for tax contingencies | 13.0 | 13.0 | ||
| Total accrued penalties for tax contingencies | 2.2 | 2.2 | ||
| Amount of unrecognized tax benefits that could decrease within the next 12 months | 9.2 | 9.2 | ||
| Decrease in unrecognized tax benefits due to the settlement of audits or resolution of administrative or judicial proceedings | 0.4 | 0.4 | ||
| Decrease in unrecognized tax benefits expiration of statute of limitations | $ 8.8 | $ 8.8 | ||
| X | ||||||||||
- Definition Estimated decrease in unrecognized tax benefits within the next twelve months due to settlement of audits or resolution of administrative or judicial proceedings. No definition available. 
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| X | ||||||||||
- Definition Estimated decrease in unrecognized tax benefits within the next twelve months due to expiration of statute of limitations. No definition available. 
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| X | ||||||||||
- Definition Gross balance of unrecognized tax benefits including interest and penalties. No definition available. 
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| X | ||||||||||
- Definition Amount of decrease reasonably possible in the next twelve months for the unrecognized tax benefit. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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| X | ||||||||||
- Definition Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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| X | ||||||||||
- References No definition available. 
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| X | ||||||||||
- Definition Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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| X | ||||||||||
- Definition Amount of statutory penalties accrued for a tax position claimed or expected to be claimed by the entity, in its tax return. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef 
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| X | ||||||||||
- Definition Amount of interest expense accrued for an underpayment of income taxes. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef 
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| X | ||||||||||
- Definition The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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