RESTRUCTURING CHARGES - Summary of Accrued Liability for the Restructuring and Related Charges (Details) $ in Thousands	3 Months Ended
Dec. 31, 2019 USD ($)
Restructuring Reserve [Roll Forward]
Restructuring reserve	$ 0
2020 restructuring charges	6,434
Cash payments	(761)
Non-cash charges	(4,160)
Restructuring reserve	1,513
Personnel related costs
Restructuring Reserve [Roll Forward]
Restructuring reserve	0
2020 restructuring charges	2,134
Cash payments	(621)
Non-cash charges	0
Restructuring reserve	1,513
Facilities, exit costs and other
Restructuring Reserve [Roll Forward]
Restructuring reserve	0
2020 restructuring charges	140
Cash payments	(140)
Non-cash charges	0
Restructuring reserve	0
Other related costs
Restructuring Reserve [Roll Forward]
Restructuring reserve	0
2020 restructuring charges	4,160
Cash payments	0
Non-cash charges	(4,160)
Restructuring reserve	$ 0

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.

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- Definition

Discloses the amount charged against the accrued restructuring reserves, or earnings if not previously accrued, during the period for the specified type of restructuring cost.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)(1)
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-Publisher FASB
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-Section 50
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-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
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-Section S99
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+ Details

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- Definition

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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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- Definition

Amount of decrease in the reserve for full or partial settlement through consideration other than cash.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 2
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