OTHER CONSOLIDATED BALANCE SHEET COMPONENTS (NON-CURRENT) - Other Non-Current Assets (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020
Acquired Indefinite-lived Intangible Assets [Line Items]
Investment in non-marketable equity securities	$ 54,980	$ 32,510
Investment in marketable equity security	0	376,258
Investment in bitcoin	200,140	50,000
Restricted cash	63,509	13,526	$ 13,286
Other	33,427	26,956
Total	352,056	499,250
Bitcoin impairment losses	19,860		$ 0
Bitcoin
Acquired Indefinite-lived Intangible Assets [Line Items]
Indefinite-lived intangible asset acquired	170,000	$ 50,000
Fair value of bitcoin investment	472,000
Amount of fair value in excess of carrying value for bitcoin investment	271,900
Bitcoin impairment losses	$ 19,900

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