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COMMITMENTS AND CONTINGENCIES (Details) $ in Millions |  | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Oct. 05, 2020 item | Sep. 30, 2020 USD ($) | Dec. 31, 2011 USD ($)
Contingency related to spectrum fees |  |  |
Commitments and contingencies |  |  |
Spectrum fees paid |  |  | $ 2.6
Litigation proceedings and disputes in Guyana |  |  |
Commitments and contingencies |  |  |
Number of competitors issued service licenses | item | 2 |  |
Legal claims regarding tax filings with the Guyana Revenue Authority |  |  |
Commitments and contingencies |  |  |
Future payments related to disputed tax assessments |  | $ 44.1 |
Accrued contingent liability |  | $ 5.0 |
Legal claims regarding tax filings with the Guyana Revenue Authority | Minimum |  |  |
Commitments and contingencies |  |  |
Percentage of return on investment ensured by the government of Guyana |  | 15.00% |

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