Condensed financial information of the parent company - Condensed statements of comprehensive income (Details) |
12 Months Ended | |||
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Dec. 31, 2025
CNY (¥)
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Dec. 31, 2025
USD ($)
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Dec. 31, 2024
CNY (¥)
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Dec. 31, 2023
CNY (¥)
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| Condensed statements of comprehensive income/(loss) | ||||
| Share-based compensation expense | ¥ (2,257,795) | ¥ (4,935,782) | ||
| General and administrative | ¥ (291,503,527) | $ (41,684,450) | (276,564,752) | (273,588,744) |
| Interest and investment income, net | 990,368,590 | 141,620,825 | 380,062,136 | 255,332,621 |
| Foreign exchange gain/(loss), net | (46,304,828) | (6,621,502) | 20,658,172 | (2,931,704) |
| Share of loss/(profit) in subsidiaries, VIEs and VIEs' subsidiaries | (18,937,550) | (2,708,034) | (4,048,792) | 3,207,384 |
| Net income before income taxes | 739,301,975 | 105,718,775 | 157,537,018 | 101,474,055 |
| Income tax expense | 30,674,579 | 4,386,405 | 65,805,623 | 62,340,516 |
| Net income | 708,627,396 | 101,332,370 | 91,731,395 | 39,133,539 |
| Other comprehensive income | ||||
| Foreign currency translation adjustment | (68,932,636) | (9,857,236) | 37,882,398 | 21,829,283 |
| Total comprehensive income | 639,694,760 | 91,475,134 | 129,613,793 | 60,962,822 |
| Parent Company | Reportable legal entity | ||||
| Condensed statements of comprehensive income/(loss) | ||||
| Share-based compensation expense | (2,257,795) | (4,935,782) | ||
| General and administrative | (32,361,695) | (4,627,661) | (40,780,739) | (19,070,062) |
| Interest and investment income, net | 474,598,252 | 67,866,647 | 189,674,053 | 104,687,566 |
| Other income | 19,514,738 | 2,790,570 | 24,463,472 | 28,626,092 |
| Foreign exchange gain/(loss), net | (45,888,491) | (6,561,967) | 20,792,611 | (545,948) |
| Share of loss/(profit) in subsidiaries, VIEs and VIEs' subsidiaries | 292,764,592 | 41,864,781 | (100,160,207) | (69,628,327) |
| Net income before income taxes | 708,627,396 | 101,332,370 | 91,731,395 | 39,133,539 |
| Net income | 708,627,396 | 101,332,370 | 91,731,395 | 39,133,539 |
| Other comprehensive income | ||||
| Foreign currency translation adjustment | (68,932,636) | (9,857,236) | 37,882,398 | 21,829,283 |
| Total comprehensive income | ¥ 639,694,760 | $ 91,475,134 | ¥ 129,613,793 | ¥ 60,962,822 |
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount, before tax, of realized and unrealized gain (loss) from foreign currency transaction. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The aggregate total of expenses of managing and administering the affairs of an entity, including affiliates of the reporting entity, which are not directly or indirectly associated with the manufacture, sale or creation of a product or product line. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of income (loss) for proportionate share of equity method investee's income (loss). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount after accretion (amortization) of discount (premium), and investment expense, of interest income and dividend income on nonoperating securities. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The portion of profit or loss for the period, net of income taxes, which is attributable to the parent. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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- Definition Amount of income (expense) related to nonoperating activities, classified as other. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of noncash expense for share-based payment arrangement. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Details
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