Share Incentive Plan - Summary of Option Activities and Changes (Details) - Employee Stock Option - CNY (¥) ¥ / shares in Units, ¥ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares, Outstanding beginning balance	62,268
Number of shares, Forfeited	(10,437)
Number of shares, Outstanding ending balance	51,831	62,268
Weighted-average exercise price, Outstanding beginning balance	¥ 560.95
Weighted-average exercise price, Forfeited	560.95
Weighted-average exercise price, Outstanding ending balance	¥ 560.95	¥ 560.95
Weighted-average remaining contractual term, Outstanding	8 years 9 months 21 days	9 years 9 months 21 days
Aggregated intrinsic value, Outstanding beginning balance	¥ 302
Aggregated intrinsic value, Outstanding ending balance		¥ 302
Weighted average grant date fair value, Outstanding beginning balance	¥ 271.90
Weighted average grant date fair value, Forfeited	271.90
Weighted average grant date fair value, Outstanding ending balance	¥ 271.90	¥ 271.90

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(3)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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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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- Definition

The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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- Definition

Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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