ACQUIRED INTANGIBLE ASSETS, NET (Summary of Acquired Intangible Assets) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019	Oct. 01, 2019
Finite-Lived Intangible Assets [Line Items]
Impairment of intangible assets	$ (7,200)	$ 0
Acquired intangible assets, net	31,800		$ 39,000
Indefinite-lived Intangible Assets Acquired	$ 31,800		$ 39,000
Intangible asset, fair value exceeding carrying value				26.00%
Intangible Asset, decline form attributable revenue	3.00%
Intangible Asset, royalty rate	5.00%			6.00%
Intangible Asset, discount rate	17.50%			1420.00%

Intangible Asset, decline form attributable revenue

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- Definition

Intangible Asset, discount rate

+ References

No definition available.

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- Definition

Intangible asset, fair value exceeding carrying value

+ References

No definition available.

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- Definition

Intangible Asset, royalty rate

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of an intangible asset (excluding goodwill) to fair value.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16373-109275

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- Definition

Amount of increase in assets, excluding financial assets and goodwill, lacking physical substance with an indefinite life, from an acquisition.

+ References

No definition available.

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- Definition

Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
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-Name Accounting Standards Codification
-Topic 350
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-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16212-109274

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