Income Taxes - Operating losses and credit carryforwards (Details) - USD ($) $ in Thousands |
Dec. 31, 2021 |
Dec. 31, 2020 |
|---|---|---|
| US Federal loss carryforwards | ||
| Operating Loss Carryforwards [Line Items] | ||
| Operating loss carryforwards | $ 52,544 | $ 55,029 |
| Tax credit carryforward, amount | 7,144 | 1,818 |
| US state loss carryforwards | ||
| Operating Loss Carryforwards [Line Items] | ||
| Operating loss carryforwards | 85,635 | 79,907 |
| Foreign Tax Authority | ||
| Operating Loss Carryforwards [Line Items] | ||
| Operating loss carryforwards | 90,826 | 73,922 |
| Tax credit carryforward, amount | $ 46,851 | $ 46,851 |