Undiscounted amount of the accrual for environmental loss contingencies.

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-Publisher FASB
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-Topic 410
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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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
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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.

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Loss Contingency, Number of Lawsuits Filed

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Disputes, Litigation and Contingencies (Details) $ in Millions	12 Months Ended
	Dec. 31, 2010 lawsuit	Sep. 30, 2020 USD ($)	Dec. 31, 2019 USD ($)
Loss Contingencies [Line Items]
Estimated litigation liability		$ 43	$ 44
Accrual for Environmental Loss Contingencies, Gross		$ 6
Neff v. Brady, et al.
Loss Contingencies [Line Items]
Number of actions filed (in lawsuits) \| lawsuit	3