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Restructuring Costs - Additional Information (Details) $ in Thousands | 1 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | ---
Feb. 29, 2020 | Jun. 30, 2020 USD ($) Employee | Dec. 31, 2019 Employee | Dec. 31, 2018 Employee
Restructuring Cost And Reserve [Line Items] |  |  |  |
Number of employees and contractors | Employee |  | 341 | 500 | 700
Percentage of reduction in employees | 10.00% |  |  |
Restructuring costs |  | $ 1,204 |  |
Operating Expenses |  |  |  |
Restructuring Cost And Reserve [Line Items] |  |  |  |
Restructuring costs |  | 1,104 |  |
Cost of revenues |  |  |  |
Restructuring Cost And Reserve [Line Items] |  |  |  |
Restructuring costs |  | $ 100 |  |

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