Income Taxes - Components of Deferred Income Tax Assets and Liabilities (Details)	Dec. 31, 2021 CNY (¥)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 CNY (¥)
Deferred tax assets:
Net loss carryforward	¥ 53,089,828	$ 8,330,952	¥ 22,229,252
Deferred revenue	115,049,834	18,053,829	132,881,621
Deferred rent	17,692,412	2,776,326	7,499,776
Bad debt expenses	30,328,801	4,759,251	7,622,390
Accrued expenses	17,687,519	2,775,558	15,971,223
Unrealised losses from equity securities	7,534,182	1,182,278	5,213,960
Valuation allowance	(59,426,713)	(9,325,349)	(24,186,707)
Total deferred tax assets	181,955,863	28,552,845	167,231,515
Deferred tax liabilities:
Depreciation of property and equipment	(6,099,754)	(957,185)	(3,990,387)
Unrealized gains from equity securities	(880,803)	(138,217)	(805,803)
Intangible assets arising from acquisition	(176,681,292)	(27,725,150)	(141,587,024)
Withholding tax on PRC earnings to be distributed	(64,929,920)	(10,188,921)	(43,191,602)
Total deferred tax liabilities	¥ (248,591,769)	$ (39,009,473)	¥ (189,574,816)

Deferred tax assets unrealized losses from equity securities.

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Deferred tax liabilities PRC dividends withholding tax.

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Deferred tax liabilities unrealized gains from equity securities.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from deferred income.

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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from accrued liabilities.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from deferred rent.

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Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary difference from allowance for credit loss on financing receivable.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences without jurisdictional netting.

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Amount of deferred tax liability attributable to taxable temporary differences from intangible assets other than goodwill.

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Amount of deferred tax liability attributable to taxable temporary differences from property, plant, and equipment.

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