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Basis of Presentation and Significant Accounting Policies - Concentration of Risk (Details) - Customer Concentration Risk - customer | 3 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jun. 30, 2020 | Jun. 30, 2019 | Jun. 30, 2020 | Jun. 30, 2019 | Dec. 31, 2019
Trade Receivables |  |  |  |  |
Concentration of Risk |  |  |  |  |
Number of major partners |  |  | 1 |  | 1
Concentration risk (as a percent) |  |  | 100.00% |  | 100.00%
Revenues |  |  |  |  |
Concentration of Risk |  |  |  |  |
Number of major partners | 1 | 3 | 2 | 1 |
Concentration risk (as a percent) | 88.00% |  |  | 88.00% |
Revenues | Partner 1 |  |  |  |  |
Concentration of Risk |  |  |  |  |
Concentration risk (as a percent) |  | 52.00% | 56.00% |  |
Revenues | Partner 2 |  |  |  |  |
Concentration of Risk |  |  |  |  |
Concentration risk (as a percent) |  | 35.00% | 40.00% |  |
Revenues | Partner 3 |  |  |  |  |
Concentration of Risk |  |  |  |  |
Concentration risk (as a percent) |  | 10.00% |  |  |

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