Income taxes - Schedule of deferred tax assets (Details) - CNY (¥) |
Dec. 31, 2025 |
Dec. 31, 2024 |
Dec. 31, 2023 |
Dec. 31, 2022 |
|---|---|---|---|---|
| Deferred tax assets | ||||
| Tax loss carried forward | ¥ 484,867,200 | ¥ 461,896,586 | ||
| Deductible temporary differences | 308,458,751 | 308,259,437 | ||
| Tax basis difference upon the restructuring in 2016 | 916,032 | 11,911,959 | ||
| Allowance for credit loss | 10,769,920 | 10,812,975 | ||
| Allowance for others | 18,460,312 | 18,868,173 | ||
| Total deferred tax assets | 823,472,215 | 811,749,130 | ||
| Less: valuation allowance | ¥ (823,472,215) | ¥ (811,749,130) | ¥ (1,111,583,535) | ¥ (1,064,015,562) |
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- Definition Deferred tax assets deductible temporary differences. No definition available.
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- Definition Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary difference from allowance for others. No definition available.
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary difference from allowance for credit loss on accounts receivable. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from restructuring reserve. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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