RESTRUCTURING CHARGES - Summary of Accrued Liability for the Restructuring and Related Charges (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2020
Restructuring Reserve [Roll Forward]
Restructuring reserve	$ 1,513	$ 0	$ 0
Q1 restructuring charges	3,104	6,434
Cash payments	(1,955)	(761)
Non-cash charges	(532)	(4,160)	(4,692)
Restructuring reserve	2,130	1,513	2,130
Personnel related costs
Restructuring Reserve [Roll Forward]
Restructuring reserve	1,513	0	0
Q1 restructuring charges	1,658	2,134
Cash payments	(1,041)	(621)
Non-cash charges	0	0
Restructuring reserve	2,130	1,513	2,130
Facilities, exit costs and other
Restructuring Reserve [Roll Forward]
Restructuring reserve	0	0	0
Q1 restructuring charges	914	140
Cash payments	(914)	(140)
Non-cash charges	0	0
Restructuring reserve	0	0	0
Other related costs
Restructuring Reserve [Roll Forward]
Restructuring reserve	0	0	0
Q1 restructuring charges	532	4,160
Cash payments	0	0
Non-cash charges	(532)	(4,160)
Restructuring reserve	$ 0	$ 0	$ 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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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

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-Publisher FASB
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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

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

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