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Basis of Presentation and Significant Accounting Policies - Concentration of Risk (Details) $ in Millions | 3 Months Ended |  |
--- | --- | --- | ---
Mar. 31, 2023 USD ($) customer | Mar. 31, 2022 customer | Mar. 10, 2023 USD ($) | Dec. 31, 2022 USD ($)
Concentration of Risk |  |  |  |
Trade receivable, net | $ 0.0 |  |  | $ 0.0
Cash and cash equivalents held at SVB | $ 3.7 |  | $ 4.5 |
Customer Concentration Risk | Revenues. |  |  |  |
Concentration of Risk |  |  |  |
Number of major partners | customer | 1 | 3 |  |
Customer Concentration Risk | Revenues. | Partner 1 |  |  |  |
Concentration of Risk |  |  |  |
Concentration risk (as a percent) | 100.00% | 64.00% |  |
Customer Concentration Risk | Revenues. | Partner 2 |  |  |  |
Concentration of Risk |  |  |  |
Concentration risk (as a percent) |  | 24.00% |  |
Customer Concentration Risk | Revenues. | Partner 3 |  |  |  |
Concentration of Risk |  |  |  |
Concentration risk (as a percent) |  | 11.00% |  |

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