Summary of Principal Accounting Policies - Reconciliations of Assets and Liabilities (Details) - 12 months ended Dec. 31, 2021 - Fair Value, Recurring	CNY (¥)	USD ($)
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Returnable consideration, Beginning balance	¥ 1,833,421
Returnable consideration, Ending balance	5,385,583
Payables for contingent consideration, Beginning balance	525,685
Available-for-sale debt investment, Beginning balance	103,701,474
Available-for-sale debt investment, Ending balance	106,493,137
Significant Unobservable Inputs (Level 3)
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Returnable consideration, Beginning balance	1,833,421
Returnable consideration, Net unrealized fair value increase recognized in earnings	3,552,162
Returnable consideration, Ending balance	5,385,583	$ 845,115
Payables for contingent consideration, Beginning balance	525,685
Payables for contingent consideration, Net unrealized fair value increase recognized in earnings	(525,685)
Available-for-sale debt investment, Beginning balance	103,701,474
Available-for- sale debt investment, Net unrealized fair value increase recognized in other comprehensive income	2,791,663
Available-for-sale debt investment, Ending balance	¥ 106,493,137	$ 16,711,097

Business combination contingent consideration liability net unrealized fair value increase recognized in earnings.

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- Definition

Returnable consideration.

+ References

No definition available.

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- Definition

Returnable consideration net unrealized fair value increase recognized in earnings.

+ References

No definition available.

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- Definition

Amount, after tax, of accumulated unrealized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14
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- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), classified as noncurrent.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
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- Definition

Amount of liability recognized arising from contingent consideration in a business combination.

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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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