Income taxes - Reconciliation of the differences between PRC statutory income tax rate and the Group's effective income tax rates (Details) |
12 Months Ended | ||
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Dec. 31, 2025 |
Dec. 31, 2024 |
Dec. 31, 2023 |
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| Income Tax Disclosure [Abstract] | |||
| Statutory tax rate | 25.00% | 25.00% | 25.00% |
| Effect of preferential tax rate | (7.00%) | (4.00%) | |
| Effect of different tax jurisdiction | 1.00% | (4.00%) | (2.00%) |
| Change in tax rate | (4.00%) | (18.00%) | |
| Prior year return-to-provision true up | 0.00% | 2.00% | |
| Non-deductible expenses and non-taxable income | (1.00%) | (4.00%) | |
| Research and development expenses additional deduction | 4.00% | 5.00% | 6.00% |
| Change in valuation allowance | (14.00%) | (5.00%) | |
| Actual income tax expense | (2.00%) | 0.00% | 0.00% |
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- Definition Percentage of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operations attributable to preferential tax rate. No definition available.
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- Definition Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Percentage of domestic federal statutory tax rate applicable to pretax income (loss). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to changes in the valuation allowance for deferred tax assets. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to changes in the income tax rates. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to statutory income tax expense (benefit) outside of the country of domicile. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to nondeductible expenses. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to revisions of previously reported income tax expense. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to research tax credit. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- References No definition available.
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