Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
(Losses) earnings before Income Taxes, Domestic	$ (21.0)	$ 952.4	$ (46.4)
Earnings (losses) before Income Taxes, Foreign	$ 178.6	171.2	$ 86.0
Foreign tax credit carryforwards expiration beginning year	2028
State net operating loss carry forward	$ 12.5	22.8
Valuation allowance	12.5	$ 22.8
Interest or penalties accrued for uncertain tax positions	$ 0.0

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible state and local operating loss carryforwards.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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The portion of earnings or loss from continuing operations before income taxes that is attributable to domestic operations.

+ References

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The portion of earnings or loss from continuing operations before income taxes that is attributable to foreign operations, which is defined as Income or Loss generated from operations located outside the entity's country of domicile.

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Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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Foreign tax credit carryforwards expiration beginning year.

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