Approximate size of referenced site.

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- Definition

Loss Contingency Reimbursement rate for qualifying costs of investigation and remediation activities.

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No definition available.

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Total costs accrued as of the balance sheet date for environmental loss contingencies.

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Amount of expense (reversal of expense) which increases (decreases) the accrual for environmental loss contingencies from revisions in estimates to existing obligations. Excludes changes related to business acquisitions, divestitures, or currency movement.

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- Definition

Carrying value of the obligation (known or estimated) arising from requirements to perform activities to remediate one or more sites, payable in twelve months or in the next operating cycle if longer.

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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.

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- Definition

The cash inflow associated with the sale of other real estate not otherwise defined in the taxonomy.

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Carrying amount as of the balance sheet date of known and reasonably estimable amounts of recoveries from third-parties pertaining to an entity's environmental remediation obligations. An entity's balance sheet may include several assets that relate to an environmental remediation obligation. Among them are the following: a. Receivables from other potentially responsible parties that are not providing initial funding; b. anticipated recoveries from insurers; and c. anticipated recoveries from prior owners as a result of indemnification agreements.

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Commitments and Contingencies (Other Contingencies) (Detail) $ in Millions		3 Months Ended	12 Months Ended
	Jun. 21, 2021 USD ($)	Sep. 30, 2014 USD ($)	Dec. 31, 2019 USD ($)	Sep. 30, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2012 a
Environmental Claims For A Site In Goodyear Arizona
Loss Contingencies [Line Items]
Accrual for Environmental Loss Contingencies, Revision in Estimates		$ 49.0	$ 18.9
Estimated liability				$ 33.5	$ 39.8
Accrued environmental loss contingencies current				$ 10.9	10.9
Loss Contingency Reimbursement Rate				21.00%
Other receivables				$ 7.3	$ 7.8
Environmental Claims For Crab Orchard National Wildlife Refuge Superfund Site
Loss Contingencies [Line Items]
Approximate size of referenced site (in acres) \| a						55,000
Goodyear Site
Loss Contingencies [Line Items]
Proceeds from sale of property	$ 8.7