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CONTINGENCIES - NARRATIVE (Details)	Apr. 08, 2020 USD ($)	Apr. 08, 2020 KRW (₩)	Mar. 27, 2019 USD ($)	Mar. 27, 2019 KRW (₩)	Jun. 30, 2021 USD ($)	Dec. 31, 2020 USD ($)	Sep. 30, 2020 USD ($)	Mar. 31, 2019 USD ($)
Loss Contingencies [Line Items]
Deposits Assets, Noncurrent					$ 12,353,000	$ 12,571,000		$ 6,900,000
Accrued Royalties							$ 500,000
LGE
Loss Contingencies [Line Items]
Payments for Deposits	$ 5,000,000.0	₩ 5,916,845,454
Samsung vs. Immersion \| Withholding taxes on royalty payments
Loss Contingencies [Line Items]
Litigation, amount awarded to other party			$ 6,900,000	₩ 7,841,324,165
Litigation, arbitration costs			$ 871,454