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Commitments and Contingencies - Additional Information (Details) - USD ($) $ in Thousands |  | 3 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | --- | ---
Dec. 11, 2019 | Mar. 31, 2021 | Mar. 31, 2020 | Dec. 31, 2020 | Jan. 01, 2021 | Jul. 31, 2020
Loss Contingencies [Line Items] |  |  |  |  |  |
Cash paid for amounts included in the present value of operating lease liabilities |  | $ 16 |  |  |  |
Contingent severance obligation accrual |  |  |  | $ 2,000 |  |
Transaction Bonus Plan ("Plan") |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |
Percentage of consideration payable | 10.00% |  |  |  |  |
Term of plan | 3 years |  |  |  |  |
Chief Executive Officer | Transaction Bonus Plan ("Plan") |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |
Percentage of ownership interest in plan | 50.00% |  |  |  |  |
Chief Financial Officer | Transaction Bonus Plan ("Plan") |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |
Percentage of ownership interest in plan | 10.00% |  |  |  |  |
Other Key Employees [Member] | Transaction Bonus Plan ("Plan") |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |
Percentage of ownership interest in plan | 40.00% |  |  |  |  |
Consultants [Member] | Transaction Bonus Plan ("Plan") |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |
Percentage of ownership interest in plan | 9.00% |  |  |  |  |
Pearson Action |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |
Contingent severance obligation accrual |  |  |  |  |  | $ 2,000
Accounting Standards Update 2016-02 |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |
Initial right-of-use asset |  |  |  |  | $ 1,179 |
Cost of Revenues |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |
Royalty expense |  | $ 362 | $ 351 |  |  |
Wireless Essential Patent Holders |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |
Royalty expire year |  | 2021 |  |  |  |
Wireless Essential Patent Holders | Maximum |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |
Royalty payment percent of net revenues |  | 5.00% |  |  |  |
Other Providers of Integrated Technologies |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |
Royalty expire year |  | 2023 |  |  |  |
Other Providers of Integrated Technologies | Maximum |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |
Royalty payment percent of net revenues |  | 5.00% |  |  |  |

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