Effective income tax rate reconciliation at preferential income tax rate.

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Percentage of effective income tax rate reconciliation withholding tax rate.

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The amount of unrecognized deferred tax liabilities.

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Withholding tax liability unrecognized for undistributed earnings.

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Amount of deferred tax liability attributable to taxable temporary differences from undistributed earnings of subsidiary and other recognized entity not within country of domicile. Includes, but is not limited to, other basis differences.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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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.

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Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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The amount of the unrecognized tax benefit of a position taken for which it is reasonably possible that the total amount thereof will significantly increase or decrease within twelve months of the balance sheet date.

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Income Taxes (Details)	12 Months Ended
Income Taxes (Details)	Dec. 31, 2024 CNY (¥)	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2024 USD ($)
Income Taxes [Line Items]
Profit tax at a rate	25.00%	25.00%	25.00%
Preferential income tax rate	15.00%
Withholding tax	10.00%
Tax losses carryforwards	¥ 502,614,634			$ 68,857,923
Unrecognized deferred tax liabilities	906,737,961			124,222,591
Uncertain tax positions	¥ 316,421,543			43,349,574
Inland Revenue, Hong Kong [Member]
Income Taxes [Line Items]
Profit tax at a rate	16.50%
State Administration of Taxation, China [Member]
Income Taxes [Line Items]
Tax liability unrecognized	¥ 11,349,180			1,554,831
Deferred tax liabilities related to undistributed earnings	¥ 33,595,045			$ 4,602,503
PRC [Member] \| Inland Revenue, Hong Kong [Member]
Income Taxes [Line Items]
Profit tax at a rate	25.00%