RESTRUCTURING CHARGES - Schedule of Restructuring Liabilities (Details) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Restructuring Reserve [Roll Forward]
Beginning Balance	$ 0	$ 3,696	$ 1,955
Restructuring charges to operations	2,657	18,908	6,022
Cash payments	(896)	(22,027)	(3,572)
Other adjustments	(41)	(577)	(709)
Ending Balance	1,720	0	3,696
Employee-Related \| Q4 FY2017 Plan
Restructuring Reserve [Roll Forward]
Beginning Balance	0	0	1,550
Restructuring charges to operations		0	729
Cash payments		0	(1,867)
Other adjustments		0	(412)
Ending Balance		0	0
Employee-Related \| FY2018 Plan
Restructuring Reserve [Roll Forward]
Beginning Balance	0	3,696	0
Restructuring charges to operations		1,017	5,085
Cash payments		(4,240)	(1,331)
Other adjustments		(473)	(58)
Ending Balance		0	3,696
Employee-Related \| VSP
Restructuring Reserve [Roll Forward]
Beginning Balance	0	0	0
Restructuring charges to operations	123	17,248	0
Cash payments	(123)	(17,329)	0
Other adjustments	0	81	0
Ending Balance	0	0	0
Employee-Related \| Q2 FY20 Plan
Restructuring Reserve [Roll Forward]
Beginning Balance	0
Restructuring charges to operations	465
Cash payments	(434)
Other adjustments	(28)
Ending Balance	3	0
Employee-Related \| Q4 FY20 Plan
Restructuring Reserve [Roll Forward]
Beginning Balance	0
Restructuring charges to operations	2,069
Cash payments	(339)
Other adjustments	(13)
Ending Balance	1,717	0
Facilities Related \| Q4 FY2017 Plan
Restructuring Reserve [Roll Forward]
Beginning Balance	0	0	405
Restructuring charges to operations		0	208
Cash payments		0	(374)
Other adjustments		0	(239)
Ending Balance		0	0
Facilities Related \| FY2018 Plan
Restructuring Reserve [Roll Forward]
Beginning Balance	$ 0	0	0
Restructuring charges to operations		643	0
Cash payments		(458)	0
Other adjustments		(185)	0
Ending Balance		$ 0	$ 0

Restructuring Charges And Other Adjustments

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- Definition

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.

+ 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)(2)
-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 17
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3367-108585

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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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=115931487&loc=d3e140904-122747

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- Definition

Amount of expense (reversal of expense) which increases (decreases) the restructuring reserve from an adjustment to a previously accrued restructuring liability.

+ 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)
-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

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-Topic 420
-SubTopic 10
-Section S99
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-URI http://asc.fasb.org/extlink&oid=115931487&loc=d3e140904-122747

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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

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