The estimated aggregate amount of losses related to respirator liability claims as of the balance sheet date.

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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- Definition

Amount of cash outflow to settle environmental loss contingencies.

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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.

+ References

No definition available.

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- Definition

Amount charged against operating income increasing loss contingency liability, after adjustments to reduce previously estimated charges.

+ References

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- Definition

Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

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- Definition

The effective date of a duly executed litigation settlement agreement.

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Commitments and Contingencies - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Mar. 31, 2020	Mar. 31, 2020	Mar. 31, 2019	Sep. 30, 2019
Respirator Liabilities [Member]
Loss Contingencies [Line Items]
Description of pending claims		The Company will pay this liability in two equal installments in Cabot’s third quarter of fiscal 2020 and first quarter of fiscal 2021.
Respirator reserve	$ 23	$ 23		$ 35
Respirator Liabilities [Member] \| Selling and Administrative Expenses [Member]
Loss Contingencies [Line Items]
Respirator charge	50
Respirator Liabilities [Member] \| Accounts Payable and Accrued Liabilities [Member]
Loss Contingencies [Line Items]
Respirator liability	65	65
Environmental Matters [Member]
Loss Contingencies [Line Items]
Reserved for environmental matters	$ 9	9		$ 13
Cash payments for environmental reserves		$ 5	$ 1