GOODWILL AND IMPAIRMENT CHARGES (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Goodwill [Line Items]
Goodwill	$ 88,099		$ 282,006
Goodwill impairment charge	191,788	$ 0
IHT
Goodwill [Line Items]
Goodwill	0		193,216
Goodwill impairment charge	191,788
MS
Goodwill [Line Items]
Goodwill	54,991		$ 55,409
Goodwill impairment charge	$ 0

Amount of loss from the write-down of an asset representing the 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 50
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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