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v3.19.2

Commitments and Contingencies - Additional Information (Details) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2019 USD ($) Employee | Mar. 31, 2018 USD ($) | Dec. 31, 2018 USD ($)
Loss Contingencies [Line Items] |  |  |
Severance obligation change in control period | 12 months |  |
Number of employee | Employee | 1 |  |
Severance obligation on event of acquisition or initial public offering. | $ 140,000 |  |
Contingent severance obligation accrual | 0 |  | $ 0
Cost of Revenues |  |  |
Loss Contingencies [Line Items] |  |  |
Royalty expense | $ 451,000 | $ 411,000 |
Wireless Essential Patent Holders |  |  |
Loss Contingencies [Line Items] |  |  |
Royalty expire year | 2021 |  |
Other Providers of Integrated Technologies |  |  |
Loss Contingencies [Line Items] |  |  |
Royalty expire year | 2023 |  |
Maximum |  |  |
Loss Contingencies [Line Items] |  |  |
Severance obligation before change in control | $ 1,057,000 |  |
Severance obligation change in control | 1,407,000 |  |
Severance obligation in event of termination with cause | $ 88,000 |  |
Maximum | Wireless Essential Patent Holders |  |  |
Loss Contingencies [Line Items] |  |  |
Royalty payment percent of net revenues | 5.00% |  |
Maximum | Other Providers of Integrated Technologies |  |  |
Loss Contingencies [Line Items] |  |  |
Royalty payment percent of net revenues | 5.00% |  |
Minimum |  |  |
Loss Contingencies [Line Items] |  |  |
Equity valuation threshold limit in severance obligation | $ 125,000,000 |  |

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