Amount of investment in equity security without readily determinable fair value.

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Amount of impairment loss on investment in equity security without readily determinable fair value.

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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.

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FINANCIAL INSTRUMENTS - Narrative (Details) - USD ($)	3 Months Ended	6 Months Ended
FINANCIAL INSTRUMENTS - Narrative (Details) - USD ($)	Jun. 30, 2020	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Schedule of Investments [Line Items]
Carrying value of investments in equity securities without readily determinable fair value	$ 5,100,000	$ 5,100,000		$ 5,100,000
Gross unrealized losses of downward adjustments to the carrying value of equity securities without readily determinable fair values	6,100,000	6,100,000
Impairment charge on equity securities without readily determinable fair value		$ 0	$ 0
Trade Name \| United Kingdom
Schedule of Investments [Line Items]
Impairment of intangible assets	$ 4,600,000