GOODWILL AND IMPAIRMENT CHARGES - Additional Information (Details) $ in Thousands		12 Months Ended
Dec. 01, 2020 USD ($)	Dec. 31, 2020 USD ($) reportingUnit	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Goodwill [Line Items]
Goodwill		$ 91,351	$ 282,006	$ 281,650
Goodwill impairment charge	$ 0	$ 191,788	0	0
Number of Reporting Units \| reportingUnit		3
IHT
Goodwill [Line Items]
Goodwill		$ 0	$ 193,216	$ 192,608
Goodwill impairment charge		$ 191,788

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
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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