Income Taxes - Movement of valuation allowance (Details) - USD ($) $ in Thousands |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2025 |
Dec. 31, 2024 |
Dec. 31, 2023 |
|
| Valuation allowance | |||
| Balance at beginning of the year | $ 108,247 | $ 109,417 | $ 101,177 |
| Changes of valuation allowance | (9,572) | (1,170) | 8,240 |
| Balance at end of the year | $ 98,675 | $ 108,247 | $ 109,417 |