Income taxes - Components of the deferred tax assets and liabilities (Details) |
Dec. 31, 2025
CNY (¥)
|
Dec. 31, 2025
USD ($)
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Dec. 31, 2024
CNY (¥)
|
Dec. 31, 2024
USD ($)
|
Dec. 31, 2023
CNY (¥)
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Dec. 31, 2022
CNY (¥)
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|---|---|---|---|---|---|---|
| Deferred tax assets: | ||||||
| Long-term investments, net of impairment | ¥ 29,294,312 | $ 4,189,031 | ¥ 20,191,218 | |||
| Advertising and market related expense carryforwards | 7,917,365 | 1,132,168 | 11,251,555 | |||
| Accounts receivable and contract assets | 76,728,374 | 10,972,012 | 16,048,561 | |||
| Guarantee liabilities | 327,632,748 | 46,850,860 | 77,314,528 | |||
| Financial guarantee derivatives | 3,856,420 | 551,461 | 159,210,663 | |||
| Loan receivable from Xiaoying Housing Loans | 14,316,731 | 2,047,265 | 14,318,757 | |||
| Loans receivable from Xiaoying Credit Loans and other loans | 255,414,788 | 36,523,829 | 220,392,866 | |||
| Operating loss carryforwards | 2,583,659 | 369,458 | 43,757,115 | |||
| Deposits to institutional cooperators | 1,274,129 | 182,198 | 1,467,822 | |||
| Lease liabilities | 11,910,124 | 1,703,125 | 10,351,392 | |||
| Others | 78,499 | 11,226 | 60,350 | |||
| Total deferred tax assets | 731,007,149 | 104,532,633 | 574,364,827 | |||
| Valuation allowance | (187,490,468) | (26,810,780) | (307,902,579) | $ (44,029,483) | ¥ (226,317,275) | ¥ (214,884,582) |
| Total deferred tax assets, net of valuation allowance | 543,516,681 | 77,721,853 | 266,462,248 | |||
| Deferred tax liabilities: | ||||||
| Property and equipment | 3,980,134 | 569,152 | 2,867,083 | |||
| Financial guarantee derivatives | 0 | 0 | 259,565 | |||
| Long-term investments, net of impairment | 17,850,275 | 2,552,555 | 4,375,796 | |||
| Right-of-use assets | 11,194,691 | 1,600,820 | 9,809,937 | |||
| Investment in Consolidated Trusts | 72,140,986 | 10,316,024 | 26,959,491 | |||
| Investment in Consolidated Partnerships | 6,572,148 | 939,805 | 31,309,764 | |||
| Undistributed earnings | 45,622,417 | 6,523,919 | 58,600,000 | |||
| Others | 471,221 | 67,384 | 526,630 | |||
| Total deferred tax liabilities | 157,831,872 | 22,569,659 | ¥ 134,708,266 | |||
| Chinese Mainland entities | ||||||
| Deferred tax assets: | ||||||
| Advertising and market related expense carryforwards | ¥ 31,669,460 | $ 4,528,673 | $ 45,006,219 |