Percentage of aggregate number of common shares reserved for future issuance based on number of outstanding shares.

No definition available.

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- Definition

After consideration of adjustments for the annual increase and other changes of options and RSUs, the available share number of the Pre-IPO Plans and 2016 Plan.

+ References

No definition available.

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- Definition

Represents information pertaining to the number of vesting schedules under the plan.

+ References

No definition available.

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- Definition

Annual percentage of vesting of share-based compensation awards.

+ References

No definition available.

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- Definition

Quarterly percentage of vesting of share-based compensation awards.

+ References

No definition available.

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- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
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- Definition

Amount of cost to be recognized for option under share-based payment arrangement.

+ References

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- Definition

Amount of noncash expense for share-based payment arrangement.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
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- Definition

Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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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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- Definition

Number of shares authorized for issuance under share-based payment arrangement.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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-Paragraph 2
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- Definition

Percentage of vesting of award under share-based payment arrangement.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Share-based Compensation - General (Details) ¥ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($) item shares	Dec. 31, 2019 CNY (¥) item shares	Dec. 31, 2018 CNY (¥)	Dec. 31, 2017 CNY (¥)
Share-based Compensation
Share-based compensation expenses	$ 2,403	¥ 16,732	¥ 27,886	¥ 35,069
Unrecognized compensation cost \| ¥		¥ 42,707
Period of recognition of compensation cost	2 years 1 month 17 days	2 years 1 month 17 days
Class A ordinary shares
Share-based Compensation
Shares reserved for future issuance (as a percent)	1.50%	1.50%
Class A ordinary shares \| Pre-IPO Plans
Share-based Compensation
Shares authorized to grant (in shares)		36,229,922
Class A ordinary shares \| 2016 Plan
Share-based Compensation
Shares authorized to grant (in shares)		4,600,000
Number of shares available after consideration and other changes	14,088,265	14,088,265
Employee stock option
Share-based Compensation
Contractual term (in years)	10 years	10 years
Employee stock option \| Minimum
Share-based Compensation
Continuous service period (in years)	3 years	3 years
Employee stock option \| Maximum
Share-based Compensation
Contractual term (in years)	10 years	10 years
Continuous service period (in years)	4 years	4 years
Employee stock option \| Pre-IPO Plans
Share-based Compensation
Number of vesting schedules \| item	3	3
Employee stock option \| Pre-IPO Plans \| Minimum
Share-based Compensation
Continuous service period (in years)	3 years	3 years
Employee stock option \| Pre-IPO Plans \| Maximum
Share-based Compensation
Continuous service period (in years)	4 years	4 years
Employee stock option \| Schedule A \| Pre-IPO Plans \| Vesting second anniversary
Share-based Compensation
Vesting percentage (as a percent)	50.00%	50.00%
Vesting period	2 years	2 years
Employee stock option \| Schedule A \| Pre-IPO Plans \| Vesting in third anniversary
Share-based Compensation
Vesting percentage (as a percent)	25.00%	25.00%
Vesting period	3 years	3 years
Employee stock option \| Schedule A \| Pre-IPO Plans \| Vesting in fourth anniversary
Share-based Compensation
Vesting percentage (as a percent)	25.00%	25.00%
Vesting period	4 years	4 years
Employee stock option \| Schedule B \| Pre-IPO Plans
Share-based Compensation
Vesting period	4 years	4 years
Vesting at each anniversary (as a percent)	25.00%	25.00%
Employee stock option \| Schedule C \| Pre-IPO Plans
Share-based Compensation
Vesting period	3 years	3 years
Vesting at each anniversary (as a percent)	33.00%	33.00%
RSUs \| 2016 Plan
Share-based Compensation
Continuous service period (in years)	6 months	6 months
Number of vesting schedules \| item	4	4
RSUs \| 2016 Plan \| Minimum
Share-based Compensation
Continuous service period (in years)	2 years	2 years
RSUs \| 2016 Plan \| Maximum
Share-based Compensation
Continuous service period (in years)	4 years	4 years
RSUs \| Schedule D \| 2016 Plan \| Vesting second anniversary
Share-based Compensation
Vesting percentage (as a percent)	50.00%	50.00%
Vesting period	2 years	2 years
RSUs \| Schedule D \| 2016 Plan \| Vesting in third anniversary
Share-based Compensation
Vesting percentage (as a percent)	25.00%	25.00%
Vesting period	3 years	3 years
RSUs \| Schedule D \| 2016 Plan \| Vesting in fourth anniversary
Share-based Compensation
Vesting percentage (as a percent)	25.00%	25.00%
Vesting period	4 years	4 years
RSUs \| Schedule E \| 2016 Plan
Share-based Compensation
Vesting period	2 years	2 years
Vesting each quarter (as a percent)	12.50%	12.50%
RSUs \| Schedule F \| 2016 Plan
Share-based Compensation
Vesting period	4 years	4 years
Vesting at each anniversary (as a percent)	25.00%	25.00%
RSUs \| Schedule G \| 2016 Plan
Share-based Compensation
Vesting period	2 years	2 years
Vesting at each anniversary (as a percent)	50.00%	50.00%
RSUs \| Schedule H \| 2016 Plan
Share-based Compensation
Vesting period	6 months	6 months
Vesting at each anniversary (as a percent)	100.00%	100.00%