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Environmental Exit Costs, Number Of Other Parties In Agreement

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Total anticipated costs associated with remediation, site restoration, postclosure, monitoring commitments, or other exit costs that may occur on the sale, disposal, or abandonment of a particular property resulting from unanticipated contamination of the assets.

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The charge against earnings in the period for known or estimated future costs arising from requirements to perform environmental remediation activities.

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Carrying amount of reserve for known or estimated probable loss from litigation, which may include attorneys' fees and other litigation costs, which is expected to be paid within one year of the date of the statement of financial position.

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Amount of loss contingency liability.

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Amount of receivable related to a loss contingency accrual. For example, an insurance recovery receivable.

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COMMITMENTS AND CONTINGENCIES (Details) $ in Thousands	1 Months Ended	9 Months Ended	12 Months Ended
COMMITMENTS AND CONTINGENCIES (Details) $ in Thousands	Sep. 30, 2016 USD ($) party	Jun. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)
Postemployment Benefits Liability [Abstract]
Expected future benefit payments		$ 7,872
Abrasive particle supply agreement
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract]
Purchase obligation		24,729
Non-water-based carrier fluid
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract]
Purchase obligation		7,863
KMG-Bernuth
Environmental Exit Cost [Line Items]
Remediation expense recognized		1,688	$ 9,494
Accrued loss contingency		866
Estimated remediation cost	$ 22,000
Number of other parties in agreement \| party	7
Estimated reserve, remaining		553
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract]
Loss Contingency, Receivable		$ 468