The estimated fair value towards promotion for service render.

No definition available.

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- Definition

Period covered by the related party long-term purchase commitment, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

Amount of beneficial interest received as consideration for transferring noncash financial asset. Includes, but is not limited to, trade receivable in securitization transaction.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4313-108586

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- Definition

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.

+ References

No definition available.

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Related party transactions (Details) - CNY (¥) ¥ in Thousands	1 Months Ended	12 Months Ended
	Jun. 30, 2014	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Related party transactions
Contribution from a shareholder				¥ 384
Beijing Dasheng Zhixing Technology Co., Ltd
Related party transactions
Fair value of promotion		¥ 535,000
Beijing Dasheng Zhixing Technology Co., Ltd \| Angel investors
Related party transactions
Term of agreement	5 years
Contribution from a shareholder		¥ 0	¥ 0	¥ 384	¥ 1,636