GOODWILL AND OTHER INTANGIBLE ASSETS - Goodwill by Business Segments (Details) $ in Thousands	12 Months Ended
Mar. 31, 2020 USD ($)
Goodwill
As of April 1, 2019	$ 594,812
Changes	23,643
As of March 31, 2020	618,455
Corporate Finance
Goodwill
As of April 1, 2019	340,282
Changes	23,643
As of March 31, 2020	363,925
Financial Restructuring
Goodwill
As of April 1, 2019	162,815
Changes	0
As of March 31, 2020	162,815
Financial and Valuation Advisory
Goodwill
As of April 1, 2019	91,715
Changes	0
As of March 31, 2020	$ 91,715

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13770-109266

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- Definition

Amount of increase (decrease) of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
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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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