Amount of beneficial interest received as consideration for transferring noncash financial asset. Includes, but is not limited to, trade receivable in securitization transaction.

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The amount by which the fair value of an investment in debt and equity securities categorized as Available-for-sale is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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Equity interest percentage for sale.

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SUBSEQUENT EVENTS - Additional Information (Details) - USD ($) $ in Millions			12 Months Ended
	Mar. 31, 2021	Dec. 17, 2020	Dec. 31, 2020
Subsequent Event [Line Items]
Operating lease agreements description			The Company has entered into operating lease agreements for principal executive office in Tokyo, Japan since November 2010, and extend the lease period for every two years. The current lease agreement will be expire in November 2021. Additionally, the Company has entered into operating lease agreements for an office in Hangzhou, Zhejiang, China with lease period expiring on July 31, 2021.
Lease expiration period			Jul. 31, 2021
UTStarcom Hong Kong Holdings Ltd. \| Eagle Field Holding Limited
Subsequent Event [Line Items]
Equity interest percentage		14.00%
Impairment loss on investment			$ 1.0
UTStarcom Hong Kong Holdings Ltd. \| Eagle Field Holding Limited \| Subsequent Event
Subsequent Event [Line Items]
Aggregate cash consideration	$ 2.1
Amount received from buyer	$ 2.1
Tokyo, Japan
Subsequent Event [Line Items]
Lease expiration period			Nov. 14, 2021