COMMITMENTS AND CONTINGENCIES (Details) - USD ($) $ in Thousands		3 Months Ended	9 Months Ended
Nov. 15, 2018	Jun. 30, 2019	Jun. 30, 2019
Postretirement Obligations in Foreign Jurisdictions [Abstract]
Expected term for benefit payments of all unfunded plans			10 years
Expected future benefit payments		$ 7,906	$ 7,906
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract]
Purchase obligation		8,859	8,859
KMG-Bernuth
Environmental Exit Cost [Line Items]
Loss contingency		4,200	4,200
Remediation expense recognized		250
Estimated remediation cost	$ 22,000
Estimated reserve, remaining		$ 1,008	$ 1,008

Amount of benefits for defined benefit plan expected to be paid over the next 10 fiscal years.

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Term of benefits from a defined benefit plan under such all unfunded plans expected to be paid.

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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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Carrying amount as of the balance sheet date of the liability for remediation, site restoration, postclosure, monitoring commitments, or other exit costs associated with 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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