Summary of Significant Accounting Policies (Details) - USD ($) $ in Thousands |
Mar. 31, 2022 |
Dec. 31, 2021 |
Mar. 31, 2021 |
Dec. 31, 2020 |
|---|---|---|---|---|
| Summary of Significant Accounting Policies | ||||
| Letters of credit | $ 1,600 | $ 1,700 | ||
| Current restricted cash included in prepaid expense and other current assets | us-gaap:PrepaidExpenseAndOtherAssetsCurrent | |||
| Restricted cash | 1,600 | $ 100 | $ 1,700 | |
| Restricted cash (non-current) | 1,573 | 1,573 | ||
| Cash, cash equivalents and restricted cash | $ 99,677 | $ 227,583 | $ 289,822 | $ 92,901 |