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Environmental Exit Costs, Number Of Other Parties In Agreement

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Amount of contractual obligation, including but not limited to, long-term debt, capital lease obligations, operating lease obligations, purchase obligations, and other commitments.

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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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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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COMMITMENTS AND CONTINGENCIES (Details) $ in Thousands	1 Months Ended	6 Months Ended	12 Months Ended
COMMITMENTS AND CONTINGENCIES (Details) $ in Thousands	Sep. 30, 2016 USD ($) party	Mar. 31, 2020 USD ($)	Sep. 30, 2019 USD ($)
Postretirement Obligations in Foreign Jurisdictions [Abstract]
Expected future benefit payments		$ 7,872
Abrasive particle supply agreement
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract]
Purchase obligation		27,497
Non-water-based carrier fluid
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract]
Purchase obligation		10,216
Abrasive particles
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract]
Purchase obligation		3,638
KMG-Bernuth
Environmental Exit Cost [Line Items]
Remediation expense recognized		593	$ 9,494
Estimated remediation cost	$ 22,000
Number of other parties in agreement \| party	7
Estimated reserve, remaining		$ 553