Property and Equipment, Net - Additional Information (Details)	12 Months Ended
Dec. 31, 2021 CNY (¥) building	Dec. 31, 2021 USD ($) building	Dec. 31, 2020 CNY (¥)	Dec. 31, 2019 CNY (¥)	Dec. 31, 2021 USD ($)
Property Plant And Equipment [Line Items]
Depreciation expense	¥ 89,617,316	$ 14,062,913	¥ 59,719,535	¥ 37,340,304
Impairment charges \| ¥	0		0	¥ 0
Property and equipment, net	¥ 1,045,356,265		668,605,661		$ 164,039,209
Asset Pledged as Collateral
Property Plant And Equipment [Line Items]
Number of properties pledges as collateral \| building	2	2
Property and equipment, net	¥ 288,313,328				$ 45,242,653

The number of properties pledges as collateral.

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- Definition

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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