Restructuring, Impairment and Other - Restructuring and Multiemployer Pension Plan ("MEPP") Reserves - Narrative (Detail) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Restructuring Cost And Reserve [Line Items]
Current restructuring reserve (included in accrued liabilities and other)	$ 26.1
Noncurrent restructuring reserve (included in noncurrent liabilities)	43.4
Accrued liabilities and other	342.4	$ 351.2
Other noncurrent liabilities	252.2	$ 272.0
MEPP withdrawal obligations related to facility closures
Restructuring Cost And Reserve [Line Items]
Accrued liabilities and other	7.1
Other noncurrent liabilities	$ 40.8

Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Amount of liabilities classified as other, due after one year or the normal operating cycle, if longer.

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Carrying amount as of the balance sheet date of known and estimated obligations associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, which are expected to be paid in the next twelve months or in the normal operating cycle if longer. Costs of such activities include those for one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, relocating employees, and costs associated with an ongoing benefit arrangement, but excludes costs associated with the retirement of a long-lived asset.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Carrying amount as of the balance sheet date of known and estimated costs associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, which are expected to be paid after one year or beyond the next operating cycle, if longer. Costs of such activities include those for one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, and relocating employees, and costs associated with an ongoing benefit arrangement, but excludes costs associated with the retirement of a long-lived asset.

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