RESTRUCTURING CHARGES - Summary of Accrual for Restructuring and Other Similar Costs (Details) $ in Thousands	12 Months Ended
Sep. 30, 2020 USD ($)
Restructuring Reserve [Roll Forward]
Charges	$ 16,047
Employee Termination Benefits
Restructuring Reserve [Roll Forward]
Accrued restructuring charges at September 30, 2019	0
Charges	19,530
Cash payments	(18,979)
Accrued restructuring charges at September 30, 2020	$ 551

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

+ References

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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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