Summary of significant accounting policies - Income Taxes (Details) - USD ($) $ in Millions |
3 Months Ended | ||
|---|---|---|---|
Mar. 31, 2022 |
Mar. 31, 2021 |
Dec. 31, 2021 |
|
| New Accounting Pronouncements or Change in Accounting Principle [Line Items] | |||
| Effective tax rate | (1.00%) | (1.00%) | |
| Operating loss carryforwards, subject to expiration | $ 0.2 | ||
| Accrued Liabilities and Other Liabilities | |||
| New Accounting Pronouncements or Change in Accounting Principle [Line Items] | |||
| Net deferred tax liability | $ 1.7 | $ 1.8 | |