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Basis of Presentation and Significant Accounting Policies - Concentration of Risk (Details) - Customer Concentration Risk - customer | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2020 | Mar. 31, 2019 | Dec. 31, 2019
Trade Receivables |  |  |
Concentration of Risk |  |  |
Number of major partners | 2 |  |
Trade Receivables | Partner 1 |  |  |
Concentration of Risk |  |  |
Number of major partners |  |  | 1
Concentration risk (as a percent) | 62.00% |  | 100.00%
Trade Receivables | Partner 2 |  |  |
Concentration of Risk |  |  |
Concentration risk (as a percent) | 38.00% |  |
Revenues | Partner 1 |  |  |
Concentration of Risk |  |  |
Number of major partners | 2 | 1 |
Concentration risk (as a percent) | 62.00% | 99.00% |
Revenues | Partner 2 |  |  |
Concentration of Risk |  |  |
Concentration risk (as a percent) | 38.00% |  |

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