v3.20.1

Summary of Significant Accounting Policies - Research and Development Costs - Additional Information (Details) - CNY (¥) | 9 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2017 | Dec. 31, 2019 | Dec. 31, 2018
Software developed for internal use |  |  |
Research and development costs |  |  |
Capitalized costs for the period | ¥ 0 | ¥ 0 | ¥ 0

X
- Definition Additions made to capitalized computer software costs during the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275 + Details
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Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- References No definition available. + Details
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Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |