Number of law suits filed.

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- Definition

Site contingency, number of sites.

+ References

No definition available.

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- Definition

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

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Amount of gain (loss) recognized in settlement of litigation and insurance claims. Excludes claims within an insurance entity's normal claims settlement process.

+ References

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- Definition

The amount recovered from insurance. These recoveries reduce costs and losses that are reported as a separate line item under operating expenses.

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Amount due in settlement of a claim for reimbursement from an insurance company when the Company has suffered a loss covered under an insurance policy.

+ References

No definition available.

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Aggregate carrying amount of the estimated litigation liability for known or estimated probable loss from litigation, which may include attorneys' fees and other litigation costs.

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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.

+ References

No definition available.

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Cash received for the settlement of litigation during the current period.

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Commitments and Contingencies - Additional Information (Detail)	1 Months Ended		9 Months Ended		12 Months Ended	132 Months Ended
	Oct. 31, 2019 USD ($)	Jul. 31, 2019 USD ($)	Sep. 30, 2020 USD ($) Site	Sep. 30, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2018 Lawsuit	Dec. 31, 2019 USD ($)
Loss Contingencies [Line Items]
Litigation reserve			$ 39,000,000				$ 56,000,000
Litigation related receivables			$ 0				0
Proceeds from insurance dispute settlements				$ 39,000,000
Gain on insurance claims				$ 37,000,000
Insurance recoveries	$ 60,000,000	$ 40,000,000			$ 42,000,000
Minimum
Loss Contingencies [Line Items]
Number of law suits filed \| Lawsuit						1,000
Superfund Sites \| Environmental Clean-up
Loss Contingencies [Line Items]
Number of sites \| Site			6
Environmental reserves			$ 17,000,000				$ 18,000,000